Left ventricular function in patients with coronary heart disease in the presence or absence of angina pectoris during exercise radionuclide ventriculography

This study compares left ventricular (LV) performance during exercise in patients with angiographically documented coronary artery disease (CAD) based on the presence or absence of angina pectoris during the index exercise tests. The patients were divided into 2 groups: Group I included 31 patients who had angina pectoris during the test and Group II included 43 who did not. Multivessel CAD was present in 21 patients (68%) in Group I and 26 patients (60%) in Group II (difference not significant [NS]). There were no significant differences between the 2 groups in age, sex, history of diabetes mellitus, history of myocardial infarction and in the exercise duration, work load, heart rate and systolic blood pressure. Exercise-induced ST-segment depression was present in 48% of the patients in Group I and in 40% in Group II (NS). The mean LV ejection fraction at rest was 52 ± 12% in Group I and 50 ± 17% in Group II (NS). There were significant differences in the 2 groups in the change from rest to exercise in ejection fraction (?4.5 ± 7.6% in Group I vs 1 ± 9.4% in Group II, p < 0.01), end-systolic volume (29 ± 38 ml in Group I vs 9 ± 23 ml in Group II, p < 0.005), the change in systolic blood pressure-to-end-systolic volume ratio (?0.1 ± 0.5 mm Hg/ml in Group I vs 0.3 ± 1.1 mm Hg/ml in Group II, p < 0.05), and wall motion score (?0.4 ± 0.6 in Group I vs 0.09 ± 0.7 in Group II, p < 0.05).Thus, asymptomatic myocardial ischemia may occur in patients with extensive CAD and be associated with abnormal exercise LV function; however, patients with symptomatic CAD have worse exercise LV function than those with asymptomatic CAD.     

Feasibility of intravascular ultrasound studies: Predictors of imaging success before coronary interventions

Background: Intravascular ultrasound (IVUS) is currently used to study lesions during transcatheter coronary therapy. However, before dilation some lesions cannot be reached or crossed with the imaging catheter. Hypothesis: This study seeks to elucidate which factors determine the feasibility of IVUS examination before coronary interventions. Methods: Accordingly, 100 consecutive patients undergoing IVUS examination before coronary angioplasty were prospectively studied. The clinical and angiographic characteristics of 77 patients with a successful IVUS study (Group A) were compared with those of 23 patients in whom IVUS was attempted but the target lesion could not be interrogated (Group B). The echogenic characteristics of the target lesion [before (n = 77) or after intervention (in 18 patients in Group B)] were also studied. Results: Patients in Group B were significantly older (62 ± 7 vs. 57 ± 10 years, p < 0.05) and more frequently had stable angina [8 (35%) vs. 9 (11%), p < 0.05]. The distribution of lesions within the coronary tree and angiographic lesion characteristics including length, eccentricity, calcification, bend location, and the American College of Cardiology/American Heart Association classification were similar in both groups. However, proximal tortuosities (>45° at end diastole) were more frequently found in Group B [20 (87%) vs. 47 (61%), p < 0.05]. In addition, by quantitative angiography, patients in Group B had smaller arteries (reference diameter 2.8 ± 0.4 vs. 3.1 ± 0.4 mm, p < 0.05) and more severe lesions (minimal lumen diameter 0.46 ± 0.24 vs. 0.65 ± 0.34 mm, p < 0.05). On IVUS, calcified lesions were more frequently visualized in Group B (61 vs. 38%, p < 0.05). On multivariate analysis, catheter size, baseline minimal lumen diameter, angiographic proximal tortuosities, and lesion calcification on imaging were independent predictors of the feasibility of IVUS studies. Conclusions: Unsuccessful IVUS studies before intervention occur more frequently (1) in vessels with proximal tortuosities or severe lumen narrowing, (2) in lesions that are calcified on IVUS, and (3) when large imaging catheters are used.     

Mechanism of left a trial enlargement related to ventricular diastolic impairment in hypertension

Background and hypothesis: Systemic hypertension is the leading cause of left ventricular (LV) hypertrophy. The present study aimed to investigate the mechanism of left atrial (LA) enlargement in patients with hypertensive heart disease during cardiac catheterization. Methods: Data were obtained from eight control subjects and seven patients with hypertensive heart disease. Left atrial and LV pressures from catheter-tip micromanometer, and LA and LV volumes from biplane cineangiograms were analyzed during the same cardiac cycle. Results: Left atrial maximal volume were 93 ± 26 ml in patients with hypertensive heart disease and 63 ± 12 ml in control subjects (p<0.05). In patients with hypertensive heart disease, time constant of LV relaxation was significantly greater than that in controls (54 ± 18 vs. 31 ± 16 ms, respectively p<0.01). Left atrial maximal volume correlated with time constant of LV relaxation (r = 0.86, p<0.01). The ratio of LV filling volume before LA contraction to LV stroke volume in patients with hypertensive heart disease was significantly lower than that in control subjects (65 ± 13 vs. 76 ± 7%, respectively p<0.05). On the other hand, the ratio of LV filling volume during LA contraction to stroke volume in patients with hypertensive heart disease was significantly higher than that in controls (35 ± 13 vs. 24± 7%, respectively p<0.05). Left atrial volume before LA contraction in patients with hypertensive heart disease was significantly larger than that in controls (74 ± 22 vs. 47 ± 10 ml, respectively, p<0.01). During LA contraction, LA work was significantly increased in patients with hypertensive heart disease compared with that in controls (274 ± 101 vs. 94 ± 42 mmHg. ml, respectively p<0.001). Left atrial work showed significant correlation with LA volume before LA contraction (r = 0.75, p <0.01). Conclusion: Left ventricular diastolic filling was impaired in patients with hypertensive heart disease. Enlargement of left atrium might be attributed to the impairment of blood flow from left atrium to left ventricle due to the increased LV stiffness.     

Characteristics and prognosis of primary liver cancer in young patients in China

To investigate the clinicopathologic characteristics of primary liver cancer (PLC) in young adults, 77 patients aged 35 or younger were compared with 603 patients older than 35 years during the same period. In the young patients, PLC showed: (1) a low incidence detected at mass survey (young 15.6% vs older 28.7%,P<0.05); (2) a low level of history of hepatitis (young 36.8% vs older 66.3%,P<0.01); (3) a high incidence of positivity for hepatitis B surface antigen (HBsAg) (young 79.2% vs older 67.6%,P<0.05); (4) a relatively low incidence of associated cirrhosis (young 64.9% vs older 90.7%,P<0.01); (5) larger tumor size (PLC>5 cm; young 87.0% vs older 73.0%,P<0.01); and (6) a more advanced stage of the disease according to the TNM classification (stage III; young 29.9% vs older 18.2%,P<0.05). It is suggested that hepatitis B virus (HBV) may play an important role in the development of PLC without associated liver cirrhosis in young patients. Close periodic surveillance of young adults who are positive for HBsAg is important to detect PLC at an early stage.     

Prognosis of culprit lesion PTCA in acute myocardial infarction for multi versus single vessel disease

We studied 417 patients undergoing single vessel culprit lesion percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction to determine the impact of disease in other vessels. Group A (189 patients, 45%) had coronary artery disease (>70% stenosis) in at least 1 additional vessel while Group B (228 patients, 55%) did not. The groups were similar in sex distribution (A = 75% male, B = 76%), number of lesions in the single culprit vessel dilated (1 lesion in 83% A, 80% B), and PTCA success (A = 92%, B = 94%) (all p = NS). Group A patients were older (63 ± 10 vs. 56 ± 11 years) and had more prior myocardial infarctions (27% vs. 7%), and more prior coronary artery bypass grafting (15% vs. 0.4%) (all p < .01). Group A patients were more likely to have repeat catheterization (48% vs. 32%, p < .005) although restenosis of the infarct-related vessel was similar (A = 24%, B = 16%) (p = NS). Group A was more likely to need angioplasty in a 2nd vessel (23% vs. 8%) and to need coronary artery bypass grafting (20% vs. 8%) (both p < .001). Cumulative mortality was higher in Group A at 1 month (10% vs. 5%), 1 year (11% vs. 6%), and long-term (13% vs. 7%). This difference appeared to be due to the impact of lower mean ejection fraction in Group A. Conclusion: Treatment of acute myocardial infarction by direct PTCA of the culprit lesion can be performed with a high likelihood of success in patients with or without multivessel coronary artery disease. Patients with multivessel disease are identified as a high risk group for whom subsequent interventional therapy may be required after the acute event. Mortality, however, is affected more by left ventricular function than by the presence of multivessel disease.     

Prolactin and thyroid hormones in patients with systemic sclerosis: correlations with disease manifestations and activity

Summary. Objective: To determine serum levels of prolactin (PRL) and thyroid hormones and to investigate the correlation between these hormones and different disease manifestations in patients with systemic sclerosis (SSc). Methods: Twenty four patients with SSc (23 women, mean age 37.7±12.7) were subjected to thyroid hormones assessment. Prolactin (PRL) was assessed in 23female patients. The patients were evaluated regarding different disease manifestations. Fifteen normal female volunteers were involved as controls. Results: Serum levels of PRL in all patients was significantly higher than controls (16.75±9.06 for patients vs. 11.6±4.5 for controls with p<0.001). Eight patients out of 23 (34.8%) showed hyperprolactinemia. In patients with diffuse SSc (dSSc), PRL levels showed significant correlation with the rate of skin tethering (r=+0.72, p<0.01) and abnormal left ventricular filling pattern (↓E/A ratio), i.e., occurrence of diastolic dysfunction (r=+0.65, p<0.05). Hyperprolactinemia in all patients correlated significantly with disease duration (r=–0.42, p<0.05).     Mean serum levels of free thyroxin (FT4) in all patients were significantly lower than the control group(7.46±2.7 for patients vs 10.47±2.5 with p<0.001). Eight out of all 24 patients (33.3%) showed hypothyroidism. In groupA (duration<3years); FT4 levels correlated significantly with Dlco% (r=+0.90, p<0.01). While in groupB (duration>3years), T4 hypothyroidism correlated significantly with hand joint restriction of motion (r=+0.66, p<0.01).    Serum levels of triiodothironine (FT3) in all patients were nonsignificantly lower than the control group (4.8±2.3 for patients vs 5.3±1.9 for controls, P=NS). Three patients out of 24 (12.5%) showed T3 thyrotoxicosis. Serum levels of T3 correlated significantly with liver enzyme elevations (r=+0.46, p<0.05) and ESR (r=+0.41, p<0.05). Conclusion: This study demonstrates the close association between PRL or thyroid hormones and some organ involvement in SSc. Correspondence to Amira A. Shahin     

Initial experience with transluminal recanalization of the recently occluded infarct-related coronary artery in acute myocardial infarction — Comparison with conventionally treated patients

In 7 patients, the recently occluded infarct-related vessel was recanalized by transluminal catheter techniques during acute myocardial infarction (Group A). 4 patients had single-vessel disease, 2 patients two-vessels disease and one, involvement of three vessels. Control angiography was performed in 6 patients, 8 days to 7 months later. Changes of coronary artery anatomy and left ventricular function were compared with a group of 9 conventionally treated patients, who were found to have occlusion of the infarct-related vessel in the acute stage (Group B). Five Group B patients had one-vessel disease, 3 patients two-vessel disease and 1 patient, involvement of all three vessels. In the chronic stage, all transluminally recanalized vessels were found to be patent in Group A. There was spontaneous recanalization of the infarct vessel in 4 of 9 Group B patients. In Group A, the length of the akinetic segment (AKS) decreased significantly (p < 0.05) from 145.4±48.5 mm to 73.2 ± 73.4 mm (mean ± SD). Volume parameters did not change significantly. In Group B, length of the AKS did not change significantly, EDVI increased significantly from 81.1 ±19.8 to 106.8±40.6 ml/m² (p < 0.05); ESVI increased significantly from 41.7 ± 13.7 ml/m² to 66.8 ± 37.9 ml/m² (p < 0.01). In the acute stage, length of the AKS and volume parameters did not differ significantly between the two groups. In the chronic stage, AKS was significantly shorter (A: 73.2 ± 63.4 mm; 144.9 ± 59 mm (p < 0.0025)) and EF was significantly higher (A: 54.6 ±11.6%; B: 40.9 ±14.5% (p < 0.05)) in Group A. Peak CPK was lower in Group A (A: 1009 ± 827 U/l; B: 1324 ± 655 U/l), but this difference did not achieve statistical significance. Results of this pilot study suggest that transluminal recanalization in the early phases of acute myocardial infarction might result in limitation of myocardial injury. However, further research will be needed to improve the technique and to test its results.     

The prevalence of risk factors and pattern of obstructive coronary artery disease in young Indians (< 45 years) undergoing percutaneous coronary intervention: A gender-based multi-center study

ObjectivesIn a retrospective study, we aimed to explore the prevalence of risk factors and trends of obstructive coronary artery disease (CAD) in Indian females <45 years of age compared to males of the same age group who underwent percutaneous coronary intervention (PCI).Materials and MethodsThis was a retrospective, observational, multi-centre study of young Indian females and males (<45 years) who underwent PCI as per the guidelines at three high-volume centres in India.ResultsIn a group of 3656 patients under the age of 45 who had PCI, 3.1% of those with obstructive CAD were young women (n = 113), while 6.9% were young men (n = 254). Traditional risk factors such as hypertension (p = 0.73), diabetes (p = 0.61), and family history of premature CAD (p = 0.63) were equally common in both genders, whereas dyslipidaemia (p < 0.001), overweight (p < 0.006), smoking (p = 0.004) and, alcoholism (p < 0.001) were more common in young males. Acute coronary syndrome was the most common clinical presentation. Single-vessel disease was common, with the involvement of the left anterior descending artery as the most common angiographic feature. The prevalence of cardiogenic shock was 4.4% in females and 4.1% in males, while the in-hospital mortality rate was 1.77% in young females and 2% in young males.ConclusionsObstructive CAD in young men and women accounted for 10% of all CAD cases requiring PCI. Although men account for the majority of patients, CAD in women under the age of 45 is not uncommon. Traditional risk factors are becoming more prevalent in younger women.     

Significance of the negative exercise test in evaluation of patients with chest pain

Fifty-three patients with chest pain and a negative exercise test at greater than 85% predicted maximal heart rate underwent coronary arteriography. Twenty-one patients (40%) had significant luminal narrowing in one or two vessels. No patient had left main disease. Pathologic electrocardiographic Q waves were present in only coronary heart disease patients (p < 0.001). There was no difference (p > 0.05) in prevalence of T wave abnormalities, chest pain or ventricular beats during exercise in patients with or without coronary disease. Analysis of sex distribution revealed that typical angina pectoris was uncommon in the women (p < 0.001) and all twenty-one coronary patients were men (p < 0.001). We conclude that in patients with chest pain and a negative exercise test, three vessel or left main coronary artery disease is unlikely. Also, women with atypical chest pain and a negative exercise test are unlikely to have a fixed coronary obstruction.     

Gender-related differences in patients with acute heart failure: Management and predictors of in-hospital mortality

Aim and methods

Gender-related differences in clinical phenotype, in-hospital management and prognosis of acute heart failure (AHF) patients have been previously reported in European and US registries. The ALARM-HF survey is the first to include a cohort of 4953 patients hospitalized for AHF in 666 hospitals in 6 European countries, Mexico and Australia.

Results

Women accounted for 37% of the study population, were older and had higher rates of de novo heart failure (45% vs 36%, p < 0.001) than men. An acute coronary syndrome (ACS) was the predominant precipitating factor in both genders, but to a lesser extent in females (30% vs 42%, p < 0.001). Between genders comparison showed higher incidence of atrial fibrillation, valvular heart disease, diabetes, obesity, anemia and depression in women (p < 0.05). Similarly, women had higher left ventricular ejection fraction (LVEF) on admission (42 ± 15% vs 36 ± 13%, p < 0.001) and systolic blood pressure (135 ± 40 mm Hg vs 131 ± 39 mm Hg, p = 0.001) than men. On the other hand, men had more often coronary artery disease, renal failure and chronic obstructive pulmonary disease (p < 0.05). Importantly, in-hospital mortality was similar in both genders (11.1% in females vs 10.5% in males, p = 0.475), and its common predictors were: systolic blood pressure at admission, creatinine > 1.5 mg/dL and diabetes. Furthermore, recent ACS, valvular heart disease and dementia contributed to prognosis in women, while LVEF, hypertension and anemia were independent predictors in men.

Conclusion

Among patients with AHF, there are significant differences in co-morbidities, precipitating factors and predictors of in-hospital mortality between genders. Nevertheless, in-hospital mortality remains similar between genders.     

Myocardial infarction in young adults: Risk factors and natural history

The risk factors and clinical course of 165 patients under 40 years of age (mean age 35) having an initial myocardial infarction (MI) (Group I) were compared to 100 patients over 40 (mean age 50) (Group II). Six risk factors were analyzed: smoking 20 pack-years, hyperlipidemia, hypertension, family history of ischemic disease, diabetes mellitus, and obesity. Only two patients in Group I and six patients in Group II had no risk factors, but the mean number of risk factors in Group I (3) differed from Group II (2) (p< 0.05). Group I had only 18% of patients without either obesity, hyperlipidemia, hypertension, or diabetes mellitus as risk factors while Group II had 41 patients with similar findings (p< 0.001). Group I had hyperlipidemia, obesity, and family history more commonly than did Group II while hypertension was more frequent in the older patients. A prior history of angina was present in nearly half of Group I and II but physical exertion just prior to MI was more common in Group I (32%) than in Group II (20%) (p < 0.05). Death at the time of MI was more frequent in Group II (p < 0.001) but congestive failure occurred in 17% of both groups. On follow-up, 45% of both groups had no complications, and the rates of subsequent MI and angina pectoris were similar in both groups. However, late death was less frequent in Group I than in Group II. Patients under 40 with myocardial infarction have more risk factors than those over 40 which may play some role in pathophysiology of young myocardial infarction. Physical exertion at the time of myocardial infarction is more common in younger patients. The complication rate is similar in both young and older myocardial infarction patients but the mortality rate, both early and late, is lower in young myocardial infarction patients.     

Prognosis of completely asymptomatic adult patients with hypertrophic cardiomyopathy

Objectives. We investigated the long-term prognosis of completely asymptomatic adult patients with hypertrophic cardiomyopathy (HC). Diagnosis of HC was suspected because of an abnormal electrocardiogram and/or cardiac murmur and confirmed by echocardiography and/or left ventricular angiography, and hemodynamic investigation.Background. Hypertrophic cardiomyopathy shows marked heterogeneity in clinical expression and prognosis. The prognosis of asymptomatic patients with HC has not been fully defined.Methods. Of 128 consecutive adult patients with HC, 58 asymptomatic patients (Group 1, mean age 42.8 years) and 70 symptomatic patients (Group 2, mean age 50.4 years) were studied to assess cardiac mortality. Mean follow-up periods were 11.0 years for Group 1 and 9.1 years for Group 2.Results. At presentation, Group 1 patients were younger and had smaller left atrial dimensions than did Group 2 patients. The annual cardiac mortality rate and the rate for sudden death alone in Group 1 were significantly lower than in Group 2 (0.9% vs. 1.9%, p < 0.05, 0.1% vs. 1.4%, p < 0.05, respectively). Although about one-third of the survivors in Group 1 had cardiac symptoms at their most recent evaluation, only one patient died suddenly compared with eight in Group 2. The annual mortality rate due to heart failure was similar in each group. Only a syncopal episode was associated with both cardiac death and sudden death for both groups combined.Conclusions. The cardiac mortality rate for completely asymptomatic adult patients with HC was very low, significantly lower than that of symptomatic patients, and there was a disproportionately low incidence of sudden death.     

Hemodialysis improves myocardial interstitial edema and left ventricular diastolic function in patients with end-stage renal disease: noninvasive assessment by ultrasonic tissue characterization

Congestive heart failure is the most common cause of mortality in patients with end-stage renal disease (ESRD). Ultrasonic tissue characterization with integrated backscatter offers a promising method for the noninvasive assessment of regional myocardial contractile performance and fibrosis. The aim of this study was to investigate the effect of hemodialysis (HD) on myocardial tissue characterization and left ventricular function in ESRD patients. We examined 26 patients with ESRD undergoing routine HD (age 63 ± 12 years, duration of HD 9.2 ± 3.2 years) and 30 patients with essential hypertension (HT; 60 ± 10 years). Routine echocardiographic parameters and the cyclic variation of ultrasonic integrated backscatter of the ventricular septum (CV-IBS) were measured. Left ventricular mass index was significantly larger in patients with ESRD than in those with HT (217 ± 56 vs 146 ± 45 g/m², P < 0.05). The indices for left ventricular diastolic function (E/A, the ratio of left ventricular peak early to late diastolic filling velocity; DT, the deceleration time of the early diastolic filling) and CV-IBS had deteriorated significantly in patients with ESRD before HD compared with those with HT (E/A, 0.6 ± 0.2 vs 0.9 ± 0.3, P < 0.05; DT, 228 ± 23 vs 184 ± 19 ms, P < 0.05; CV-IBS, 9.0 ± 1.3 vs 12.4 ± 0.9 dB, P < 0.05), possibly reflecting interstitial fibrosis. In patients with ESRD, HD reduced calculated left ventricular mass index by 19% (before HD, 217 ± 56 vs immediately after HD, 176 ± 45 g/m², P < 0.05) and CV-IBS by 19% (9.0 ± 1.3 vs 7.3 ± 1.1 dB, P < 0.05), that possibly reflected improvement of interstitial edema. HD also significantly improved indices for left ventricular diastolic function (E/A, 0.6 ± 0.2 vs 0.9 ± 0.2, P < 0.05; DT, 228 ± 23 vs 188 ± 21 ms, P < 0.05). HD improves myocardial interstitial edema and left ventricular diastolic function in patients with ESRD. Noninvasive assessment of ultrasonic tissue characterization is useful in defining the pathophysiological changes of ventricular myocardium in patients with ESRD. Received: December 17, 2001 / Accepted: April 19, 2002 Correspondence to O. Hirono     

Coronary angioplasty in high-risk patients with left main coronary stenosis: Results from the national registry of elective supported angioplasty

To assess the outcome of PTCA in circulatory supported patients with left main coronary artery (LMCA) stenosis, the National Registry of Elective Supported Angioplasty data bank was searched. Patients entered in the registry were considered high-risk PTCA and the PTCA was performed using percutaneous cardiopulmonary bypass (PCPB). Criteria for high risk was left ventricular ejection fraction <25% or a target lesion supplying >50% of functioning myocardium. Of 455 patients entered in the registry, 61 (13.3%) had LMCA stenosis >60%. There were 42 patients in whom the PTCA target vessel was the LMCA (PTCA-LMCA) and 19 in whom it was vessel(s) other than the LMCA (PTCA-OTHER). The mean age was similar in the 2 groups (65 ± 10 vs. 68 ± 9yrs, p = ns). The left ventricular ejection fraction (LVEF) was higher in PTCA-LMCA than in PTCA-other (38 ± 16% vs. 27 ± 16%, p <0.05). The number of vessels dilated/patient was higher in PTCA-LMCA than in PTCA-OTHER (2.1 ± 1.0 vs. 1.1 ± 0.3, p <0.001). There were a total of 10 in-hospital deaths (16%) in patients with LMCA >60% stenosis. This exceeds the mortality of the patients with <60% LMCA stenosis entered in the registry (4.5%, p <0.001). There were 6 in-hospital deaths (14%) in PTCA-LMCA and 4 (21%) in PTCA-OTHER (p = ns). PTCA in the presence of LMCA stenosis, whether the LMCA is the target vessel or not, carries a very high risk, independent of LVEF or the number of vessels dilated, despite the use of PCPB.     

Left Ventricular Response to Exercise after Transmural Anterior Myocardial Infarction*

Abstract: Left ventricular response to exercise after transmural anterior myocardial infarction. A. T. H. Tan, N. Sadick, P. J. Harris, J. Morris and D. T. Kelly. Aust. N.Z. J. Med., 1982, 12 , pp. 489–494. The purpose of this study was to determine the effect of a previous myocardial infarction on the left ventricular response to exercise and to see how this response is modified by the presence of multivessel versus single vessel coronary artery disease. Twenty-seven patients with a past history of transmural anterior myocardial infarction underwent rest and exercise gated equilibrium blood pool imaging. All 27 patients had a total occlusion of the left anterior descending coronary artery and akinesis of the anterior wall of the left ventricle. Sixteen patients had isolated, left anterior descending artery occlusion (Group A). Eleven patients had multivessel disease with 70% or greater stenosis of one or more major coronary arteries in addition to the total left anterior descending artery occlusion (Group B). Seventeen subjects with atypical chest pain and normal exercise test were selected as controls. Seven Group B patients but no Group A patients developed angina and/or ischaemic ST changes with exercise. Control subjects achieved an average 94±2% (mean) of their predicted work capacity whereas the post-infarct patients had a diminished work capacity (Group A 73±6%, P <0.001; Group B 65±5%, p< 0.001). Control subjects showed an increase in ejection fraction (EF) from rest (0.53 ±0.02) to peak exercise (0.63±0.02). This increase was primarily due to a 33±6% decrease in end systolic volume since the end diastolic volume did not change significantly from rest to peak exercise (-1.4±4%). In Group A patients, EF did not change from rest (0.32±0.03) to peak exercise (0.30±0.03) because there was a similar increase in end-diastolic volume (76±4%) and end-systolic volume (19±4%). However, in Group B patients EF decreased from 0.32±0.03 to 0.23±0.02 (p<0.01) because of a disproportionate increase in endsystolic volume (45 ± 13%) compared to enddiastolic volume (27± 7%). When patients with abnormal resting left ventricular function due to previous myocardial infarction exercise there is little change in the ejection fraction and the increase in cardiac output is heart rate dependent. If additional myocardial ischaemia develops the ejection fraction and stroke volume decrease due to a disproportionate increase in endsystolic volume.     

Left atrial size and left ventricular function in coronary artery disease: An echocardiographic-angiographic correlative study

M-mode echocardiography was used to determine left atrial size in 100 patients with coronary artery disease undergoing cardiac catheterization. Patients were divided in two groups on the basis of left atrial diameter (≥ 40 mm in 40 patients and < 40 mm in 60). Patients with larger left atria had a higher frequency of electrocardiographic evidence of left atrial abnormality (p < 0.01) and myocardial infarction (p < 0.001). Pulmonary capillary wedge and left ventricular end-diastolic pressures were higher (p < 0.005) in patients with larger left atria. An abnormal end-diastolic volume (>100 ml/M²) was observed in 13 patients with enlarged left atria compared to none with normal left atrial size (p < 0.001). Triple vessel disease was more frequent (63% vs 32%) and single vessel disease less frequent (10% vs 37%) in patients with larger left atria (p < 0.005). Abnormal left ventricular contractile patterns were noted in 45% of patients with normal left atrial diameters compared to 80% in those with an enlarged left atrium (p < 0.001). An abnormally low ejection fraction (< 0.5) was observed in 25% and 80%, respectively, in patients with normal and enlarged left atria (p < 0.001). Of 58 patients with normal ejection fractions, only 17% had left atrial diameters ≥40 mm compared to 71% of 42 patients with abnormally low ejection fractions (p < 0.001). Of 18 patients with left atrial diameters > 42 mm, only two had normal ejection fractions. The mean ejection fraction for patients with left atrial diameters <40 mm was 0.63 ± 0.13 compared to 0.41 ± 0.18 for those with diameters ≥40 mm (p < 0.001). The sensitivity, specificity, and predictive value for an enlarged left atrium in identifying an abnormal ejection fraction were, respectively, 71, 83, and 75%. These findings indicate that M-mode echocardiographic left atrial enlargement is a useful marker of advanced hemodynamic and anglographic abnormality in patients with coronary artery disease.     

The effect of iron overload in the hearts of patients with beta-thalassemia

Background and hypothesis: An important complication of beta-thalassemia is iron deposition in cardiac tissues resulting in fibrosis and dysfunction. Our aim was the investigation of the possible clinical effect of iron loading in the heart of patients with beta-thalassemia prior to the appearance of symptoms of depressed systolic function. Methods: Thirty-five patients with beta-thalassemia, of whom 24 had the major type (Group 1) and 11 had the intermedia type (Group 2) were studied. Eleven age- and gender-matched controls were also studied (Group 3). All patients were evaluated echocardiographically and were shown to have normal left ventricular systolic function and dimensions. Serum ferritin, atrial natriuretic peptide (ANP), left atrial diameter (LAD), peak early mitral inflow velocity (E), peak late mitral inflow velocity (A), E/A ratio, deceleration time of the mitral inflow E wave (DT), and isovolumic relaxation time (IVRT) were measured. Results: Univariate analysis showed that both groups of patients had similarly increased LAD and ANP plasma levels. Group 1 had a higher E/A ratio (2.27 ± 0.88) SS than Group 2 (1.69 ± 0.47, p = 0.05) and Group 3(1.50 ± 0.38, p = 0.01). Serum ferritin was significantly higher in Group 1 (3.526 ± 0.352) than in Group 2 (2.808 ± 0.288, p < 10^–5) and Group 3 (2.139 ± 0.124, p<10^–5). Multivariate analysis showed that ANP is a factor that is affected by the LAD and E/A ratio and that serum ferritin levels affect the LAD and E/A ratio. Conclusions: Although LAD and ANP levels are increased in patients with beta-thalassemia, the increased serum ferritin levels of patients seem to affect left atrial size and E/A ratio. ANP secretion is consecutively affected by these factors.     

Circadian rhythm of autonomic activity in patients with obstructive sleep apnea syndrome

Background and hypothesis: Although the immediate effects of sleep apnea on hemodynamics and the neurological system have been studied, little is known about the circadian rhythm of heart rate variability in patients with obstructive sleep apnea syndrome (OSAS). The purpose of the present study was to investigate the effects of sleep apnea on the autonomic activity during daytime, which may play some role in the pathogenesis of cardiovascular complications in OSAS. Methods: We studied 18 middle-aged male patients with OSAS and 10 age-matched control subjects. Patients with OSAS were classified according to the severity of OSAS: patients with an apnea index (AI) < 20 were considered to have mild OSAS (Group 1, n = 8) and patients with an AI≥ 20 were considered to have severe OSAS (Group 2, n = 10). Heart rate variability was calculated from the 24-h ambulatory electrocardiograms by the Fourier transformation. Power spectra were quantified at 0.04-0.15 Hz [low frequency power (LF)ln(ms²)] and 0.15-0.40Hz [high frequency power (HF)ln(ms²)]. The HF component and the ratio of LF to HF were used as indices of the parasympathetic and sympathetic activity, respectively. Results: The circadian rhythms of the LF, HF, and LF/HF ratio differed significantly in Group 2 compared with Group 1 and control subjects (p<0.05). Hypertension (>160/95 mm Hg) was found in 7 (70.0%) of 10 patients in Group 2, and in 1 (12.5%) of 8 patients in Group 1. Echocardiographic evidence of left ventricular hypertrophy (LVH) (an interventricular septal thickness or a left ventricular posterior wall thickness ≥ 12 mm) was found in 3 (30.0%) of 10 patients in Group 2, and in 1 (12.5%) of 8 patients in Group 1. The mean HF from 4 A.M. to 12 noon was significantly lower in Group 2 than in Group 1 and the control group, and it correlated significantly with the lowest nocturnal SaO₂ (r = 0.58, p<0.05). The mean LF/HF ratio during the same period was significantly higher in Group 2 than in Group 1 and the control group, and it correlated significantly with total time of the nocturnal oxygen saturation <90% (r = 0.64, p<0.005) and the lowest nocturnal SaO₂ (r = 0.56, p<0.05). Ventricular tachycardia was found in the early morning in one patient, ST-T depression in two patients, and sinus arrest in two patients in Group 2. Conclusion: These findings suggest that sleep-disordered breathing associated with severe oxygen desaturation might influence heart rate variability not only during sleep but also during daytime. OSAS per se might contribute to altered circadian rhythm in autonomic activity leading to the development of cardiovascular diseases.     

Normal angiogram after myocardial infarction in young patients:: A prospective clinical-angiographic and long-term follow-up study

This is an observational study in which we compared the clinical characteristics and the long-term course of young patients having acute myocardial infarction and angiographically normal coronary arteries and young patients showing significant coronary artery disease. In 87 patients aged ≤40 years who suffered an acute myocardial infarction, enrolled in a prospective study over a period of 6.5 years, coronary anatomy was determined by angiography within a month of admission. The risk factors, clinical data, ventricular function and the long-term outcome were compared between patients with normal angiograms (Group 1, n=12) and patients with coronary artery disease (Group 2, n=75). Patients in Group 1 had a lower number of risk factors associated with them (17% vs. 64% with >1 risk factor, P<0.005), were younger (32±5 vs. 36±4, P<0.01), lighter smokers (25% vs. 55% for ≥2 packs per day, P<0.05), had less frequent hypertension (0 vs. 25%, P<0.05), hypercholesterolemia (17% vs. 52%, P=0.02) and had a lower mean total cholesterol level (201±42 vs. 245±60 mg/100 ml, P<0.05) than patients in Group 2. They also had a more common onset of their infarction during heavy physical exertion (67% vs. 17%, P<0.001). A history of previous myocardial infarction, infarct location, global left ventricular function and regional wall motion were similar in both groups. After a mean follow-up period of 41±23 months, no patient died or had a second myocardial infarction in Group 1, and 4 patients had died in Group 2. The appearance of angina, less frequent in Group 1 than Group 2, tended to correlate with the extension of the coronary artery disease. We concluded that young patients with myocardial infarction have good prognosis irrespective of the coronary anatomy, although patients with normal coronary angiograms had less risk factors and less frequent new ischaemic events.     

Effects of new calcium channel blocker of niludipine on the coronary hemodynamics,diastolic properties,and metabolic responses to tachycardia stress in patients with coronary disease

A new calcium channel blocker, niludipine, was administered intravenously to nine patients with coronary artery disease in order to investigate its effects on left ventricular systolic and diastolic function, coronary sinus blood flow, and myocardial lactate metabolism. Coronary sinus pacing was performed in all patients and produced angina in six patients. Niludipine increased the resting heart rate from 75 ± 3 beats/min (mean ± SEM) to 82 ± 3 (NS) and decreased the left ventricular systolic pressure from 155 ± 4.7 mm Hg to 134 ± 2.8 (p < 0.05). Coronary sinus blood flow increased by 9%(NS). During pacing after niludipine, clinical improvement occurred in the six patients who had initially experienced angina. The extent of ischemic ST segment depression was decreased (?1.56 ± 0.27 mm to ?0.78 ± 0.38, p<0.02) and myocardial lactate metabolism was improved. When pacing was terminated, niludipine suppressed the elevation of left ventricular end-diastolic pressure compared to pretreatment values (16.2 ± 2.5 mm Hg vs 8.5 ± 0.9, p < 0.05) and decreased the left ventricular time constant T(26.4 ± 3.6 msec to 20.2 ± 2.4, p < 0.05). The results suggest that niludipine appears to be beneficial in reducing systolic and diastolic work of the left ventricle during pacing induced angina without a significant change in total coronary sinus blood flow. Niludipine appears to have less of a hypotensive and reflex tachycardic effect than nifedipine.