Early left ventricular dysfunction and chelation therapy in thalassemia major

Exercise radionuclide angiography was used to assess the incidence of subclinical abnormalities of left ventricular function in 23 asymptomatic patients with thalassemia major. Left ventricular ejection fraction (LVEF) at rest was normal in 18 patients and abnormal in 5. A normal LVEF response during exercise was shown in only 5 of the patients with normal resting left ventricular function. A normal response during exercise occurred more often in those patients who had received a smaller transfusional iron load and had a lower serum ferritin level (p less than 0.05). Twelve of the twenty-three patients were receiving chelation therapy with subcutaneous deferoxamine. Ejection fraction at rest was normal in 11 of these patients. During exercise a normal ventricular response was shown in 4 patients. After 1 year of intensive chelation therapy in these 12 patients, left ventricular function was reassessed. A normal exercise response was seen in an additional 4 patients; 3 of these showed an increase in peak exercise LVEF, and in the remaining patient no change of peak exercise LVEF was shown. The response during exercise was unchanged in 3 patients and had deteriorated in 1 patient.     

Evaluation of late cardiotoxicity with pulsed Doppler echocardiography in patients treated for Hodgkin's disease

Summary. The impact of valvular, myocardial and pericardial abnormalities on cardiac haemodynamics in patients treated for Hodgkin's disease with COPP/ABVD with and without mediastinal irradiation was determined in 49 patients 2–10 years after induction therapy. Diagnostic procedures to evaluate cardiac function consisted of history, physical examination, exercise bicycle stress test, M-mode two-dimensional and pulsed Doppler echocardiography. No patient reported symptoms related to cardiomyopathy, and only one of the 49 had evidence of coronary heart disease. Pericardial thickening was seen on echocardiograms in 19/49 patients (38.8%), valvular thickening in 21/49 (42·9%), and reduced fractional shortening in 9/49 (18·4%). The Doppler-derived mean E and A (±SD) of transmitral flow were 0·75 ± 0·14 m/s and 0·56 ± 0·09 m/s, respectively, in patients receiving chemotherapy and 0·81 ± 0.19 m/s and 0·63 ± 0·20 m/s in those with additional mediastinal irradiation. There was no statistically significant difference between mean E and A in transmitral flow in patients treated for Hodgkin's disease and control subjects. Furthermore, the transtricuspid and hepatic vein flow velocities did not differ significantly. Although the present study demonstrates high frequencies of pericardial and valvular thickening in patients treated for Hodgkin's disease with the COPP/ABVD regimen with or without mediastinal irradiation, it showed no impact on cardiac flow velocities. The abnormalities might thus be of minor clinical relevance in these patients.     

Effect of rate-dependent left bundle branch block on global and regional left ventricular function

Seven subjects with rate-dependent left bundle branch block (RDLBBB) and 13 subjects with normal conduction (control group) underwent upright bicycle exercise radionuclide angiography to determine the effects of the development of RDLBBB on global and regional left ventricular function. Six of the seven subjects with RDLBBB had atypical chest pain syndromes; none had evidence of cardiac disease based on clinical examination and either normal cardiac catheterization or exercise thallium-201 scintigraphy. Radionuclide angiograms were recorded at rest and immediately before and after RDLBBB in the test group, and at rest and during intermediate and maximal exercise in the control group. The development of RDLBBB was associated with an abrupt decrease in left ventricular ejection fraction (LVEF) in six of seven patients (mean decrease 6 +/- 5%) and no overall increase in LVEF between rest and maximal exercise (65 +/- 9% and 65 +/- 12%, respectively). In contrast, LVEF in the control group was 62 +/- 8% at rest and increased to 72 +/- 8% at intermediate and 78 +/- 7% at maximal exercise. The onset of RDLBBB was associated with the development of asynchronous left ventricular contraction in each patient and hypokinesis in four of seven patients. All patients in the control group had normal wall motion at rest and exercise. These data indicate that the development of RDLBBB is associated with changes in global and regional ventricular function that may be confused with development of left ventricular ischemia during exercise.     

Prediction of left ventricular function during supine bicycle ergometer exercise in angina-free patients with old myocardial infarction

We investigated whether or not left ventricular function during dynamic exercise in angina-free patients with old myocardial infarction could be estimated using resting left ventricular function and noninvasive parameters determined during exercise. We studied 70 patients with old myocardial infarction by measuring hemodynamic parameters during supine multistage bicycle ergometer exercise. Coronary arteriography and left ventriculography were performed: then the left ventricular ejection fraction and left ventricular end-diastolic volume were measured. The parametric changes (delta) between rest and peak exercise were determined. Significant positive correlations were observed between cardiac index (CI) at rest and at peak exercise (r = 0.62, p less than 0.001), as well as between pulmonary artery wedge pressure (PAWP) at rest and at peak exercise (r = 0.72, p less than 0.001). Multiple regression analysis indicated that CI and PAWP at peak exercise as dependent variables were best described by the equations: CI at peak exercise = 1.074 [CIrest] +0.031 [delta HR] + 0.004 [ExD] + 0.018 [LVEF] - 1.560 (r = 0.79, p less than 0.001), PAWP at peak exercise = 0.994 [PAWPrest] - 0.181 [LVEF] + 0.203 [delta DBP] -0.076 [delta HR] -21.488 (r = 0.80, p less than 0.001). These data suggested that CI and PAWP during dynamic exercise in angina-free patients with old myocardial infarction could be predicted using noninvasive parameters, such as increments of blood pressure and heart rate as well as exercise duration, together with data on resting left ventricular function, such as resting CI, resting PAWP, and resting left ventricular ejection fraction (LVEF).     

Study of left ventricular function at rest and post-exercise with thallium-201 myocardial scintigraphy synchronized with ECG

ECG-gated Thallium 201 myocardial scintigraphy provides a simultaneous evaluation of left ventricular perfusion and function. The aims of this study were to determine the changes in left ventricular ejection fraction (LVEF) after exercise and at rest 4 hours after exercise and to compare the results with changes in myocardial perfusion and the severity of the coronary artery disease. Sixty-four men with myocardial ischaemia on scintigraphy who had undergone coronary angiography showing significant lesions within 3 months, were compared with 38 normal men. The ejection fraction was calculated with a validated programme (QGS). The change in LVEF between the post-exercise and resting measurement 4 hours after exercise (delta LVEF) was compared in the normal and ischaemic groups (+7 +/- 6.8% vs -5.6 +/- 5%, p < 0.001). The extent of the ischaemia (percentage myocardium unperfused) was significantly greater in the 34 patients who had an over 5% reduction in LVEF on exercise compared with the 30 others who has a less than 5% reductionin LVEF (11.8 vs 6.3%, p < 0.001). There was a linear correlation between the degree of ischaemia and delta LVEF in the 30 patients without a history of infarction (r = -0.76, p < 0.01). The delta LVEF also correlated with the number and site of the coronary lesions. The authors conclude that in this male population, ECG-gated Thallium 201 myocardial scintigraphy can demonstrate a decrease in LVEF after exercise in ischaemic coronary patients whereas it increases in normal subjects. This decrease in LVEF on exercise is correlated with the extent of ischaemia and the severity of the coronary disease and should therefore be taken into account in patient management.     

Alternating non-cross-resistant combination chemotherapy or MOPP in stage IV Hodgkin's disease. A report of 8-year results

In patients with stage IV Hodgkin's disease mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) was randomly tested against MOPP alternated monthly with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). All 88 evaluable patients had not received chemotherapy and 25 had had a relapse after primary irradiation. The complete remission rate with MOPP/ABVD was 88.9% (40 of 45 patients), and with MOPP, 74.4% (32 of 43 patients). The 8-year results show that MOPP/ABVD was superior to MOPP in terms of freedom from progression (64.6% compared to 35.9%; p less than 0.005), relapse-free survival (72.6% compared to 45.1%; p less than 0.01), total survival (83.9% compared to 63.9%; p less than 0.06), and survival of complete responders (94.8% compared to 77.1%; p = 0.04). The delivery of MOPP/ABVD was not associated with an increased incidence of major toxicity. The early sequential rotation of two equally effective and non-cross-resistant drug combinations can substantially improve the likelihood of cure in patients with Hodgkin's disease.     

Long-term effect of mexiletine on left ventricular function and relation to suppression of ventricular arrhythmia.

The effects of oral mexiletine on left ventricular (LV) ejection fraction (EF) and ventricular arrhythmias--and a possible relation between these effects--were evaluated during 3 months of therapy in 29 patients with chronic ventricular premature complexes (VPCs) and a moderately reduced to normal LVEF by 24-hour Holter monitoring and by radionuclide ventriculography at rest and during maximum tolerable exercise testing. After an average titration period of 13 days, a mean daily mexiletine dose of 739 mg was maintained throughout the treatment. At the end of titration and after 3 months of treatment, patients with a baseline LVEF less than or equal to 40% (group 2) responded with a median reduction of the hourly VPC rate by 90 and 81%, respectively, compared with 79 and 72% in those with a baseline LVEF greater than 40% (group 1). Couplets and runs of ventricular tachycardia were almost completely suppressed in nearly all patients. A single patient had a proarrhythmic increase in VPCs during treatment. Compared with baseline, there were no significant changes in resting or exercise LVEF after 1 or 3 months of treatment in either of the 2 groups of patients. No correlation was found between treatment-induced changes in arrhythmia frequency and in resting EF. No symptoms of congestive heart failure developed. The study confirms that long-term use of mexiletine is efficacious and relatively free of cardiac depressant effects even in patients with diminished LV function.     

Fifteen-year secondary leukaemia risk observed in 761 patients with Hodgkin's disease prospectively treated by MOPP or ABVD chemotherapy plus high-dose irradiation

Between 1972 and 1988, 869 adult patients received MOPP (mechlorethamine, vincristine, procarbazine and prednisone; 462 patients) or ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine; 373 patients) and subsequent high-dose irradiation for Hodgkin's disease. Nine patients developed a leukaemia after MOPP and four after ABVD; 11 patients were diagnosed as acute non-lymphoblastic leukaemia (ANLL) and two as acute lymphoblastic leukaemia (ALL). Both cases of ALL were observed after ABVD and were associated with a 11q23 translocation. The 15-year actuarial risk of secondary leukaemia was 2.4% for the whole group of patients, 3.4% after MOPP and 1.3% after ABVD. For the MOPP subgroup, the risk of leukaemia was significantly associated with the extent of irradiation: 2.4% for limited irradiation and 13.9% for extended irradiation (P < 0.001). For the ABVD subgroup, this risk remained low (1.3%) whatever the type of irradiation. Concerning ANLL, the MOPP regimen was significantly associated with a higher risk: 3.4% versus 0.7% for ABVD (P相似文献   

Biventricular function in sickle-cell anemia: Radionuclide angiographic and thallium-201 scintigraphic evaluation

Left ventricular (LV) and right ventricular (RV) function were evaluated at rest and during exercise using radionuclide ventriculography in 10 patients, aged 19–53 years, with sickle-cell anemia (SCA). Seven patients were in New York Heart Association functional class I and 3 were in class II. The resting LV ejection fraction (EF) was normal in 9 patients and the resting RVEF was normal in 4. LV dilation and high cardiac output were observed in 6 patients at rest. The LVEF during exercise was normal in all 10 patients, whereas only 2 patients had normal RVEF at rest and during exercise. The LVEF was lower in patients with SCA at rest (54 ± 4 % versus 61 ± 6%, p < 0.001) and exercise (66 ± 4% versus 74 ± 6%, p < 0.001) than in 42 age-matched normal subjects. Rest thallium-201 images from 9 patients showed abnormal RV uptake in 8 and normal LV uptake in 8.Thus, in adult patients with SCA, LV function was normal during exercise in all patients and at rest in all but 1 patient. The LVEF, however, was lower than that in age-matched normal subjects. RV function was abnormal in most patients at rest and during exercise. RV thallium-201 uptake suggested pressure or volume overload (or both), most likely due to pulmonary vaso-occlusive complications of the disease.     

Hemodynamic response to supine exercise in patients with chest pain and normal coronary arteriograms

During the past year, the response to supine exercise was included in the hemodynamic evaluation of almost all patients referred to our laboratory because of chest pain. Seventeen of 58 patients with chest pain were found to have normal coronary arteriograms, normal resting intracardiac pressures, and a normal left ventriculogram. Nine of these 17 patients had an abnormal exercise response, as evidenced by a significant increase in the left ventricular end diastolic pressure. The degree of left ventricular dysfunction was minimal, since exercise cardiac output increased normally, stroke volume was maintained during exercise, and the calculated left ventricular end-diastolic volumes and ejection fractions were normal. Atypical chest pain was present in all but one subject, who had typical angina pectoris. In addition, the group shared features such as arrhythmias, dyspnea, and non-specific electrocardiographic abnormalities, which are common to all forms of cardiomyopathy. We suggest that this patient group may frequently be mislabeled as having no cardiac disorder when no further evaluation of cardiac function, other than resting intracardiac pressures and a left ventriculogram, is carried out.     

Cyclic delivery of MOPP and ABVD combinations in Stage IV Hodgkin's disease: rationale, background studies, and recent results

This paper summarizes the experience achieved at the Cancer Institute of Milan with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy in various stages of Hodgkin's disease, with special emphasis on the cyclic delivery of mechlorethamine, vincristine, prednisone, and procarbazine (MOPP) and ABVD in the primary treatment of stage IV disease. Six cycles of ABVD yielded a complete remission (CR) rate (71%) similar to that of MOPP (63%). ABVD combined with radiotherapy in 153 patients with stage IIB, IIIA, or IIIB disease was superior to MOPP plus radiotherapy in the CR induction (94% vs 79%, P less than 0.01), particularly in the presence of nodular sclerosis histology (P less than 0.03) and B symptoms (P = 0.01), as well as in the relapse-free survival of patients with pathologic stage IIIA disease (ABVD, 100%; MOPP, 68%; P = 0.02). Total survival was similar between the two treatment groups, but, compared to MOPP, ABVD chemotherapy was associated with a lower incidence of delayed toxic effects such as azoospermia, prolonged amenorrhea, and cancerigenesis. ABVD induced CR in 59% of 54 patients resistant to MOPP; 37.5% of the complete responders remain alive and disease-free at 5 years. The cyclic delivery of MOPP and ABVD was significantly superior to that of MOPP alone in terms of CR (92% vs 71%; P = 0.02), freedom from disease progression (70% vs 37%; P less than 0.0001), and relapse-free survival (77% vs 47%; P less than 0.01) at 5 years. Toxic effects were similar between the two treatment groups, but there was a higher incidence of vomiting and alopecia following ABVD chemotherapy; in the group given MOPP alone, one patient who had previously failed extensive irradiation developed acute nonlymphocytic leukemia. ABVD is confirmed to be an effective regimen that is non-cross-resistant to MOPP and devoid of late morbidity. Therefore, its administration, when alternated monthly with MOPP, offers the possibility to improve the cure rate of Hodgkin's disease.     

Effects of severity of mitral stenosis on left and right ventricular function at rest and during exercise

Few studies have assessed the effect of severity of mitral stenosis (MS) on ventricular function. Using equilibrium radionuclide ventriculography to measure ejection fraction and volume changes, 63 patients were studied during supine, symptom-limited exercise. To more carefully assess the 12 patients with MS and impaired left ventricular function, 2 groups of patients were formed. Group I (n = 51) had a normal (less than 50%) resting left ventricular (LV) ejection fraction (EF) and group II (n = 12) had an abnormally low (less than 50%) resting LVEF. Both groups were divided into mild (greater than 1.4 cm2), moderate (1.1-1.4 cm2) and severe (less than 1.0 cm2) MS. There were no differences in mean rest or exercise LVEF for group I. Exercise LVEF increased significantly (p less than 0.05) from rest with mild MS, but not with moderate or severe MS. The decrease in exercise LVEF was due to a decrease in exercise end-diastolic volume of 9 +/- 23% and 15 +/- 18% for moderate and severe MS, respectively. Exercise end-systolic volume decreased normally for all degrees of MS severity. Exercise right ventricular (RV)EF did not increase for any degree of MS severity due to an increase in end-systolic volume. All patients in group II had an RVEF of less than 40%. For this group, severity of MS had no effect on resting LVEF and the response to exercise was similar to group I. We conclude that in patients with MS, resting LVEF is unaffected by MS severity whereas exercise LVEF decreases with increased severity of MS due to impaired diastolic filling.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of molsidomine on global and regional left ventricular function at rest and during exercise in patients with angina pectoris

Although the antianginal properties of molsidomine are well-established, little is known about its effects on global and regional left ventricular dysfunction secondary to myocardial ischemia. In the present study, left ventricular performance was assessed by radionuclide ventriculography at rest and during exercise in 15 patients with coronary artery disease (CAD) and angina pectoris before and after the administration of 2 mg molsidomine sublingually. Gated blood pool studies were performed for evaluation of left ventricular ejection fraction (LVEF) and regional wall motion by analyzing amplitudes and phases of the first Fourier coefficient of regional time–activity curves. In contrast to normal subjects, during the control study period LVEF in patients with CAD decreased from 50.9% at rest to 42.7% during exercise (p<0.01). After molsidomine the resting values of LVEF increased slightly from 50.9% to 55.7% (p<0.05). Exercise values of LVEF increased from 42.7% to 51.3% (p<0.01). This is usually associated with amelioration of anginal pain and ischemic ST depression in the precordial ECG (0.15 mV vs. 0.09 mV; p<0.01). Before molsidomine, regional wall motion deteriorated from rest to exercise in 11 of 15 patients. These wall motion abnormalities usually expressed themselves as newly developed regions of left ventricular dysfunction (8 patients) or as accentuation of pre-existing contraction disturbances (3 patients). After molsidomine, regional wall motion did not show consistent changes at rest. Comparison during exercise showed enhanced regional function in 10 of the 15 patients after administration of the drug. At rest a slight but significant increase in heart rate was measured following molsidomine, whereas exercise heart rate remained unchanged. Only minor changes in systolic blood pressure occurred after molsidomine (rest, 143 mmHg vs. 134 mmHg; p<0.05; exercise, 177 mmHg vs. 174 mmHg; p>0.10). In conclusion, assessment of left ventricular performance at rest and during exercise in patients with CAD revealed significant improvement of global and regional left ventricular function, indicating reduction of myocardial ischemia. These effects may result primarily from reduction of left ventricular wall tension.     

Risk of infertility in patients with Hodgkin's disease treated with ABVD vs MOPP vs ABVD/MOPP.

The gonadal function of 38 patients with Hodgkin's disease (HD) treated with MOPP chemotherapy (12 patients), ABVD (9 patients) and alternating MOPP/ABVD (17 patients) has been retrospectively investigated with semen analysis. Median age of patients was 25 years (range 16-41 years). Azoospermia was found in all patients from the MOPP group (100%), in 3 of the ABVD group (33%) and in 13 of the MOPP/ABVD group (76%). After temporary oligospermia full recovery of spermatogenesis was observed in 67% of patients treated with ABVD, versus 25% of MOPP-treated patients following a prolonged period of azoospermia and oligospermia. Patients receiving MOPP/ABVD scheme had complete recovery of testicular function after oligospermia in 24% of cases. These results confirm the higher gonadal toxicity of the MOPP regimen as compared to others such as ABVD without alkylating agents.     

Relationship of thallium-201 myocardial perfusion pattern to regional and global left ventricular function with exercise

Thallium-201 redistribution pattern after exercise was related to rest and exercise left ventricular regional and global function, measured by radionuclide ventriculography, in 61 patients, 50 with coronary artery disease (CAD). Sixteen patients had exclusively transient thallium defects, suggesting ischemia: in this group, mean left ventricular ejection fraction (LVEF) was 65% at rest, falling to 58% during exercise (p < 0.01). Eight patients had exclusively persistent thallium defects, suggesting scar: LVEF was unchanged during exercise, 58% to 59%. LVEF increased during exercise in the 17 patients without exercise thallium defects, seven with CAD: 66% to 73% (p < 0.05). Individual LV wall segments which exhibited translent or persistent thallium defects contracted abnormally both at rest and during exercise as compared to LV segments without exercise thallium defects. We conclude that: (1) only transient thallium defects rellably predict worsening left ventricular global function during exercise; (2) both transient and persistent thallium defects can be associlated with resting dyssynergy; and (3) in some CAD patients, apparent hypoperfusion does not necessarlly predict left ventricular dysfunction during exercise.     

Effect of oral propranolol on rest and exercise left ventricular ejection fraction, volumes, and segmental wall motion in patients with angina pectoris. Assessment with equilibrium gated blood pool imaging.

The effect of oral propranolol on left ventricular ejection fraction, left ventricular volumes, cardiac output, and segmental wall motion was assessed with multigated blood pool imaging both at rest and during supine exercise in 15 patients with angina pectoris. Propranolol had no effect on resting left ventricular ejection fractions. Before propranolol, they did not change during exercise, whereas after propranolol the ejection fractions increased slightly. Exercise left ventricular ejection fractions increased with propranolol in three patients with resting left ventricular ejection fractions of less than 40 per cent. More specifically, left ventricular end-diastolic volume index, end-systolic volume index, stroke volume index, and cardiac index were not altered significantly at rest or during exercise by propranolol. Exercise left ventricular ejection fractions were increased in five and unchanged in eight patients by propranolol. Those patients with increases in left ventricular ejection fractions had a greater change in left ventricular end-diastolic volume indices and a greater change in left ventricular end-systolic volume indices during exercise while on propranolol. Left ventricular segmental wall motion was not altered significantly during exercise by propranolol. We conclude that: (1) Left ventricular functional responses to propranolol during exercise are heterogeneous and not easily predicted; (2) propranolol causes no consistent deterioration in exercise left ventricular ejection fraction even in patients with resting ventricular ejection fractions less than 40 per cent; (3) increased exercise left ventricular ejection fraction with propranolol is contributed to by significant increases in end-diastolic volume during exercise; and (4) gated blood pool imaging is a useful method for characterising rest and exercise left ventricular ejection fractions and left ventricular volumes during propranolol therapy.     

Improved left ventricular performance during exercise with verapamil or nifedipine in patients with chronic stable angina

To examine the effects of chronic oral therapy with verapamil, 120 mg three times a day, and nifedipine, 20 mg four times daily, on left ventricular ejection fraction and regional wall motion at rest and exercise, 10 patients with chronic stable angina pectoris underwent serial rest and exercise radionuclide angiography. Pre drug control study revealed a resting left ventricular ejection fraction (LVEF) of 0.62 +/- 0.08, falling to 0.54 +/- 0.12 at peak exercise (p less than 0.05). Wall motion score deteriorated from a resting value of 13.8 +/- 2.3 to 10.6 +/- 1.8 (p less than 0.01) with exercise. Patients were subsequently randomized to verapamil or nifedipine for 4 weeks each in an open-labeled crossover design. Rest and exercise radionuclide angiography were repeated at the end of each 4-week period. Neither verapamil nor nifedipine had a significant effect on resting LVEF (verapamil LVEF = 0.61 +/- 0.10, nifedipine LVEF = 0.64 +/- 0.02). Likewise, they had no significant effect on resting wall motion score (verapamil = 14.2 +/- 2.2, nifedipine = 14.4 +/- 1.6). Both verapamil and nifedipine significantly increased LVEF at peak exercise (verapamil = 0.63 +/- 0.09, nifedipine = 0.65 +/- 0.08, p less than 0.05 vs pre drug control) and improved peak exercise wall motion score (verapamil = 13 +/- 1.9, nifedipine = 13.8 +/- 1.6, p less than 0.05 vs pre drug control). Both drugs significantly reduced maximal ST depression at peak exercise and prolonged exercise duration. Episodes of angina and nitroglycerin use were also significantly reduced. In summary, verapamil and nifedipine improved left ventricular performance at exercise in patients with angina pectoris.     

Cardiac performance in thyrotoxicosis: analysis of 10 untreated patients

This study attempts to define cardiac performance at rest and during exercise in patients with untreated thyrotoxicosis. We studied 7 women and 3 men, aged 23 to 59 years (40 +/- 10, mean +/- standard deviation [SD]) and compared the results with those obtained in 12 normal subjects. In patients with thyrotoxicosis, the rhythm was sinus and the only untoward symptom was palpitations; the resting electrocardiographic results were normal in 8 patients and showed left ventricular hypertrophy in 2 patients; the left ventricular ejection fraction and volumes (measured by radionuclide ventriculography) were normal at rest. During exercise, 1 patient had dyspnea and 7 had leg fatigue; 2 were asymptomatic. Also, 7 patients had greater than or equal to 5% increase in left ventricular ejection fraction, 2 had no change, and 1 had a decrease. In all 10 patients, the exercise ejection fraction was greater than or equal to 60%. All normal subjects had a greater than or equal to 5% increase in ejection fraction during exercise. There were no significant differences at rest between patients with thyrotoxicosis and normal subjects in blood pressure, ejection fraction, end-diastolic volume, stroke volume, end-systolic volume, or cardiac output, but the heart rate was significantly higher in patients with thyrotoxicosis (91 +/- 10 versus 80 +/- 12 beats/min, p less than 0.05). During exercise, there were no significant differences between patients with thyrotoxicosis and normal subjects in blood pressure, end-diastolic volume, stroke volume, end-systolic volume, or cardiac output. The exercise ejection fraction was significantly lower in patients with thyrotoxicosis than in normal subjects (68 +/- 10% versus 75 +/- 4%, p less than 0.05). Cardiac performance is normal at rest in patients with thyrotoxicosis, but during exercise abnormal left ventricular reserve occurs in some patients.     

Exercise and rest technetium-99m-tetrofosmin lung uptake: correlation with left ventricular ejection fraction in patients with coronary artery disease

Increased lung uptake of thallium-201 (Tl-201) and technetium-99m (Tc-99m) MIBI in myocardial perfusion imaging is a reliable marker of left ventricular dysfunction. The goal of our study was to establish whether the lung-to-heart (L/H) uptake ratio with a newer cardiac imaging agent, Tc-99m tetrofosmin, can also provide valuable information about left ventricular function. We studied 60 patients with recent coronary artery diseases (CAD) undergoing first-pass radionuclide ventriculography to calculate left ventricular ejection fraction (LVEF) and myocardial perfusion imaging to calculate the L/H ratio. Group A consisting of 30 CAD patients with higher LVEF (> or =40%) had a significantly lower L/H ratio than group B consisting of 30 CAD patients with abnormal LVEF (<40%) during exercise and rest. In groups A and B, the exercise and rest L/H ratios did not differ significantly. However, a statistically significant inverse correlation was found between the L/H ratio and LVEF during exercise and rest among the 60 patients. L/H ratios, measured by 99mTc-tetrofosmin imaging, provide clinically useful information with which to predict left ventricular dysfunction in CAD patients.     

Impaired left ventricular functional reserve in hypertensive patients with left ventricular hypertrophy

To determine whether patients with hypertension and especially those with left ventricular hypertrophy have subtle changes in cardiac function, we measured the increase in left ventricular ejection fraction and in systolic blood pressure to end-systolic volume index ratio with exercise in 40 hypertensive patients and 16 age-matched normotensive volunteers. Twenty-two hypertensive patients without hypertrophy had normal end-systolic wall stress at rest and exercise responses. In contrast, the 18 patients with echocardiographic criteria for left ventricular hypertrophy demonstrated a significant increase in end-systolic wall stress at rest compared with normal subjects (69 +/- 16 vs. 55 +/- 15 10(3) x dyne/cm2, p less than 0.05) despite having normal resting left ventricular size and ejection fraction. In patients with left ventricular hypertrophy, the increase in ejection fraction with exercise was less than in the normotensive control subjects (7 +/- 7 vs. 12 +/- 8 units, p less than 0.05), and delta systolic blood pressure to end-systolic volume with exercise was reduced (3.3 +/- 3.8 vs. 8.3 +/- 7.7 mm Hg/ml/m2, p less than 0.05). The hypertensive patients with hypertrophy displayed a shift downward and to the right in the relation between systolic blood pressure to end-systolic volume ratio and end-systolic wall stress compared with control subjects and hypertensive patients without left ventricular hypertrophy. Thus, hypertensive patients with left ventricular hypertrophy by echocardiography and normal resting ejection fraction exhibit abnormal ventricular functional responses to exercise. This finding may have implications in identifying patients at higher risk for developing heart failure.