Radionuclide angiographic assessment of left ventricular function during exercise in patients with a severely reduced ejection fraction

To study the effect of exercise on left ventricular ejection fraction in patients with congestive cardiomyopathy and the relation of the response to the origin of the myocardial dysfunction, 30 patients with a severely reduced ejection fraction (30 percent or less) were evaluated with radionuclide angiography. Group I consisted of 16 patients with ischemic cardiomyopathy and a mean (± standard deviation) resting ejection fraction of 22.3 ± 6.1 percent. Group II was composed of 14 patients with primary cardiomyopathy and a mean resting ejection fraction of 19.3 ± 4.7 percent. The mean age, left ventricular end-diastolic pressure, cardiac index and resting left ventricular ejection fraction of Groups I and II were similar; however, the change in the ejection fraction during similar levels of exercise differed significantly. The mean exercise ejection fraction decreased to 16.7 ± 6.8 percent in Group I, but increased to 24.6 ± 6.4 percent in Group II (p < 0.001). Thus, exercise usually results in a directionally opposite change in left ventricular ejection fraction depending on the origin of the congestive cardiomyopathy.     

Apparent reduction of aortic and left heart chamber size in atrial septal defect

Although it is widely held that the size of the aorta and left atrium is diminished in patients with atrial septal defect, few data are available to support this contention. Therefore, aortic and left heart chamber dimensions in 24 patients with documentation of an atrial septal defect at cardiac catheterization were compared with those of 22 normal persons. The data were obtained using echocardiography, cineangiography and qualitative estimation of aortic size from chest X-ray films. Aortic size was similar in the patients with an atrial septal defect and normal subjects (1.7 cm/m² for both groups on angiography). Although the aortic diameter was estimated to be small in 12 of the 24 patients with an atrial defect on chest X-ray films, no difference existed in aortic measurements on echocardiography or angiography in patients judged to have normal as opposed to those judged to have reduced aortic size. Although the left atrial echographic dimension tended to be slightly greater in the patient group than in normal subjects (2.2 versus 1.9 cm/m²), this difference was not statistically significant. The echographic ratio of left atrial to aortic size was greater in the patient group (1.3 versus 1.1) (P < 0.02). Stroke index was similar in the two groups (37.5 versus 42.8 ml/m² with the dye-dilution technique and 35.1 versus 36.3 ml/m² on angiography). Although echocardiographic left ventricular diastolic dimension was slightly smaller in the patient group than in normal subjects (2.5 versus 3.0 cm/m²) (P < 0.02), diastolic volume index on angiography was similar in the two groups (50.1 versus 52.9 ml/m²). Thus, these data do not support the conventional belief that, because of a reduced stroke volume, the size of the aorta and left atrium is diminished in patients with an atrial septal defect.     

Echocardiography in aortic root dissection and dilatation.

Six patients with aortic root dissection proved by angiography, surgery or autopsy, and six patients with aortic root dilatation were studied by echocardiography. Echocardiography was diagnostic in five or six patients with dissection and suggestive in the sixth, disclosing anterior and posterior dissection in three, anterior dissection in one and posterior dissection in one. The recording of a double echo in the aorta was the diagnostic feature. Angiography was diagnostic in four of the six patients, yielded a false negative result in one and was not performed in one. Six patients with dilatation had an enlarged aortic root by echocardiography. Left ventricular size, stroke volume, ejection fraction, aortic regurgitant flow and velocity of circumferential fiber shortening were calculated in 11 patients. Echocardiography was extremely helpful in the diagnosis, management and follow-up in patients with aortic dissection or dilatation.     

Anuloaortic ectasia: A clinical and echocardiographic study

Twenty-six patients with an aortic root diameter ≥ 3.7 cm by 2-dimensional echocardiography (2-D echo) were studied. Group I consisted of 14 patients (mean age 50 ± 14 years) with idiopathic anuloaortic ectasia and group II consisted of 12 patients (mean age 60 ± 12 years) with secondary causes of aortic root dilatation. Patients in group I had a significantly larger aortic root diameter at the level of the aortic valve (5.0 ± 0.7 cm) and 2 cm above the aortic valve (5.3 ± 1.2 cm) as assessed by echo than did patients in group II (4.1 ± 0.3 and 4.4 ± 0.4 cm, respectively, p < 0.025). The diameter of descending thoracic aorta was slightly larger in patients in group II (3.1 ± 0.8 vs 2.7 ± 0.5 cm, difference not significant). Over a mean follow-up period of 18 months, in group I, aortic dissection developed in 3 patients and severe aortic regurgitation and congestive heart failure in 2; 7 patients had aortic root grafting, aortic valve replacement or both. The 3 patients in group I with aortic dissection had an aortic root diameter ≥ 5.3 cm, but 4 asymptomatic patients also had a diameter > 5 cm. Only 1 patient in group II required surgery for aortic dissection. Thus, 2-D echo is useful in identifying and following high-risk patients with anuloaortic ectasia.     

Diagnosis of acute aortic dissection by echocardiography

Until recently, the diagnosis of aortic dissection rested on aortography. The purpose of this study was to evaluate the diagnostic value of echocardiography in that disease and its ability to inform on the extent of the dissection and on the presence of associated lesions. Twenty-six patients (mean age 64 +/- 10 years) admitted for suspected aortic dissection were explored by echocardiography and the results were compared with those of angiography and/or anatomical findings. Echocardiography provided the diagnosis in 14 of the 16 patients with aortic dissection and excluded it in the remaining 10 patients. The sensitivity and specificity of the method were 87.5 p. 100 and 100 p. 100 respectively. The type of dissection was correctly determined in 90 p. 100 of the patients whose aorta had been totally explored by echocardiography. Aortic regurgitation and pericardial effusion were detected in 81 p. 100 and 50 p. 100 respectively of patients with aortic dissection. These results confirm the diagnostic value of echocardiography in dissection of the aorta. The extent of the lesion can only be evaluated when the whole of the aorta is visualized. The echocardiographic diagnosis is easier when the ascending aorta is involved (type I), while in type III aortic dissection there is a risk of missing a retrograde lesion of the aorta and confusing this type with type I. In this study two kinds of intimal flap motion were observed: in the first one the motion was independent of that of the aorta, while the second one resembled a division of the aortic, wall the motion of which is parallel to that of the aorta.     

Enhancement of left ventricular function by glucose-insulin-potassium infusion in acute myocardial infarction

Twenty-eight patients admitted to the hospital with suspected acute myocardial infarction underwent baseline studies within 12 hours of onset of symptoms. Patients were then randomized to receive control infusion (0.45 percent sodium chloride at 20 ml/hour) (15 patients) or glucoseinsulin-potassium infusion (300 g glucose, 50 units regular insulin, 80 mEq KCl/liter water at 1.5 ml/kg per hour) (13 patients) for 48 hours. All patients received 0.45 percent sodium chloride for 2 more days. Coronary arteriograms and left ventriculograms were obtained in 26 (93 percent) of 28 patients 2 to 3 weeks after infarction.Radionuclide ejection fraction improved during glucose-insulin-potassium infusion (49 ± 4 to 55 ± 5 percent, p < 0.01). Before discharge, the angiographic ejection fraction was greater in the glucose-insulin-potassium recipients than in control patients (43 ± 3 versus 35 ± 3 percent, p < 0.05). Radionuclide ejection fraction decreased in all control patients during the study (42 ± 4 to 37 ± 3 percent, p < 0.0005) and did not change significantly in the treated group (49 ± 4 to 43 ± 5 percent, p = not significant [NS] by paired t test). Regional wall motion analysis revealed an increase in ejection fraction in the “infarcted zone” in the treated group only (44 ± 7 to 54 ± 8 percent, p < 0.01) during glucose-insulin-potassium infusion. There was also a significant decrease in ejection fraction in the “noninfarcted zone” in the control group only (50 ± 4 to 45 ± 4 percent, p < 0.01).During experimental infusion pulmonary arterial end-diastolic pressure decreased in the glucose-insulin-potassium group (17 ± 2 to 12 ± 2 mm Hg, p < 0.01) without changing significantly in the control group. Calculated end-diastolic and end-systolic volume indexes changed in opposite directions in the two groups during experimental infusion (end-diastolic volume index 80 ± 5 to 90 ± 9 ml/m² in the control group versus 70 ± 9 to 55 ± 6 ml/m² in the treated group, p < 0.005 for change from baseline value between groups and the end-systolic volume index 48 ± 6 to 55 ± 8 ml/m² in the control group versus 39 ± 8 to 26 ± 5 ml/m² in the treated group (p < 0.01 for change from baseline value between groups).These data suggest that glucose-insulin-potassium infusion after acute myocardial infarction in human beings (1) increases global ejection fraction, (2) Increases ejection fraction in the “infarcted zone” without changing ejection fraction in the “noninfarcted zone”, and (3) decreases pulmonary arterial end-diastolic pressure and end-diastolic and end-systolic volumes.     

Improved longevity due to reduction of sudden death by aortocoronary bypass in coronary atherosclerosis: Prospective evaluation of medical versus surgical therapy in matched patients with multivessel disease

To evaluate the efficacy of coronary bypass surgery in reduction of sudden death, the prognosis of 286 similar patients with multivessel coronary stenosis was studied prospectively and the results of medical therapy (Group I, 114 patients) were compared with those of surgical therapy (Group II, 172 patients) after cardiac catheterization and coronary arteriography. During 39 months' evaluation of both groups, mortality from congestive heart failure and noncardiac causes did not differ (Group I, 14 percent; Group II, 8 percent) (P greater than 0.05). Sudden was evaluated in the remaining 217 patients (Group I, 96; Group II, 121 patients) who were matched for age (Group I, 52 years; Group II, 51 years); duration of overt coronary disease (Group I, 3.8 years; Group II, 4.0 years); angina pectoris (Group I, 83 percent; Group II, 95 percent); prior myocardial infarction (Group I, 77 percent; Group II, 74 percent); and congestive heart failure (Group I, 30 percent; Group II, 23 percent) (all P greater than 0.05). In addition, the prevalence of coronary risk factors was the same (P greater than 0.05) in both groups (hypertension, cigarette smoking, diabetes mellitus, lipid abnormalities and family history of coronary disease). Importantly, arteriography and catheterization established a similar extent and location of major coronary arterial stenoses and of ventricular dysfunction; two vessel disease (Group I, 32 percent; Group II, 33 percent) and three vessel disease (Group I, 68 percent; Group II, 67 percent); left ventricular end-diastolic pressure (Group I, 13; Group II, 14 mm Hg);cardiac index (Group I, 2.85; Group II, 2.91 liters/min per m2); and coronary collateral vessels (Group I, 58 percent; Group II, 61 percent) (all P greater than 0.05). Fifty-six percent of patients in Group II had multiple bypass grafts and a late patency rate (average 21 months) of 87 percent of one or more grafts. During subsequent prospective evaluation of over 3 years, bypass surgery provided greater symptomatic benefit of improved functional capacity (Group I, 12 percent; Group II, 69 percent) (P less than 0.05) and complete anginal relief (Group I, 30 percent; Group II, 60 percent) (P less than 0.05). Moreover, bypass surgery was associated with marked reduction in sudden death (Group I, 24 percent; Group II, 6 percent) (P less than 0.05). Thus, in patients with multivessel coronary disease carefully matched for clinical factors, hemodynamics, atherogenic precursors and coronary pathoanatomy, effective aortocoronary bypass surgery appeared to prolong survival by decreasing the incidence of sudden death, possibly by a decrease of unexpected fatal arrhythmias.     

Value of noninvasive techniques for predicting early complications in patients with clinical class II acute myocardial infarction

Twenty-six consecutive patients with acute clinical class II myocardial infarction were prospectively evaluated to assess the ability of two-dimensional echocardiography and gated equilibrium radionuclide angiography to predict early morbidity and mortality. Within 48 hours of the onset of symptoms, right heart catheterization, two-dimensional echocardiography and radionuclide angiography were performed. Serious in-hospital complications developed in 7 patients (27%, Group I), while the remaining 19 patients (Group II) had no complications. Mean left ventricular stroke work index was the only hemodynamic variable that differed significantly between Group I and Group II (28 +/- 8 [standard deviation] vs. 39 +/- 13 g-m/m2, respectively, p less than 0.02). Also, Group I compared with Group II had a significantly lower mean left ventricular ejection fraction by two-dimensional echocardiography (26 +/- 5 vs. 51 +/- 10%, p less than 0.001) or by radionuclide angiography (29 +/- 9 vs. 46 +/- 12%, p less than 0.001). Similarly, Group I had a higher average wall motion index than Group II by both techniques (2.2 +/- 0.2 vs. 1.7 +/- 0.3, p less than 0.001 by two-dimensional echocardiography, and 2.1 +/- 0.3 vs. 1.7 +/- 0.3, p less than 0.001 by radionuclide angiography). Selected stepwise multiple regression analysis demonstrated that left ventricular ejection fraction or wall motion index, by two-dimensional echocardiography or radionuclide angiography, had additional value to a history of prior myocardial infarction for predicting in-hospital complications in patients with class II infarction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intracardiac surgery in infants under age 3 months: Incremental risk factors for hospital mortality

During the 13 year period from January 1967 to July 1980, the hospital mortality rate for open intracardiac operations in infants in the first 3 months of life was 43 percent (75 deaths among 194 patients), higher than the 22 percent mortality rate (35 deaths in 161 patients) for closed operations in the same age group. The mortality rate was lower late in the experience (p = 0.0001). Poor preoperative condition of the patient increased the mortality rate 87 percent in patients preoperatively acidotic or in shock [preoperative class V]and 22 percent in patients with moderate or severe symptoms but without recent hemodynamic deterioration (preoperative class II or III). The presence of major associated cardiac lesions increased hospital mortality (p < 0.0001). The hospital mortality rate was highest (59 per cent) in infants less than age 1 month, possibly in part because of their sensitivity to the damaging effects of cardiopulmonary bypass. This hypothesis is supported by the association of a long period of cardiopulmonary bypass with increased hospital mortality (p = 0.05) and of total circulatory arrest during profound hypothermia with decreased mortality (p = 0.05). Most deaths (72 percent) occurred in association with acute postoperative cardiac failure. The length of cardiac ischemia (aortic cross-clamping time) was directly related to the probability of cardiac death, unless cold cardioplegia was used. Thirteen percent of the hospital deaths were associated with acute postoperative respiratory failure. Current mortality rates in typical cases without acute hemodynamic deterioration is estimated from these data to be 7 percent (70 percent confidence limits 4 to 12 percent), as a result of the scientific advances made over this period of time. Research into mechanisms of the damaging effects of cardiopulmonary bypass should further improve results in these very young patients.     

Transient electrocardiographic changes in patients with unstable angina: Relation to coronary arterial anatomy

The relation between the spontaneous electrocardiographic changes and coronary arterial anatomy in unstable angina pectoris was examined in 97 patients with coronary artery disease and transient electrocardiographic changes during chest pain. Sinus rhythm was maintained during pain in all patients. Heart rate increased significantly in 61 percent (mean ± standard error of the mean 72 ± 2 to 93 ± 2 beats/min, probability [p] < 0.001) and was unchanged or decreased in 39 percent of patients (73 ± 2 to 72 ± 2 beats/min; p = not significant) during pain. S-T segment changes developed in 97 percent of patients, of whom 42 percent had S-T segment elevation and 55 percent S-T depression. The magnitude of the S-T segment shift was greater in patients with triple vessel disease (2.2 ± 0.4 mm) than in those with double (1.5 ± 0.1 mm) or single (1.4 ± 0.1 mm) vessel disease (p < 0.05). In 43 patients with single vessel disease S-T segment elevation developed in 78 percent of those with right coronary artery disease and in only 9 percent of those with left circumflex disease (p < 0.02). Maximal S-T segment changes were more frequent in the inferior leads in patients with right coronary artery disease (56 percent) and in the anterior leads in patients with left anterior descending (65 percent) and circumflex (64 percent) disease (p < 0.05).Thus, patients with coronary artery disease and unstable angina maintain regular sinus rhythm during chest pain, and the heart rate usually increases but may be unchanged or decreased in a significant proportion. S-T segment elevation is common in these patients and the magnitude of the S-T segment shift is related to the extent of the underlying coronary disease. This study suggests that the type and distribution of the repolarization changes are a reflection of the location and severity of the atherosclerotic process.     

Two-dimensional and Doppler echocardiographic evaluation of aortic aneurysm and dissection

Ten patients with nondissecting aortic aneurysm and 10 with aortic dissection proved by angiography, surgery or both, were studied by real-time, 2-dimensional echocardiography. Multiple transducer positions were used to visualize various aortic segments so that a composite image of the aorta could be formulated. Using this comprehensive approach, the site, size and extent of all nondissecting aneurysms were correctly delineated (2 ascending aorta, 3 ascending aorta plus aortic root and 5 aortic arch with brachiocephalic involvement). In all patients with aortic dissection, the condition was identified by the presence of prominent, flap-like, undulating motion of the inner dissected wall or marked parallel wall widening (greater than or equal to 15 mm) and correctly categorized into DeBakey type I (4 cases), II (2 cases) or III (4 cases). Pulsed Doppler studies were useful in diagnosing reopening of dissection in a patient with previous surgical obliteration of the false channel.     

Accuracy of biplane and multiplane transesophageal echocardiography in diagnosis of typical acute aortic dissection and intramural hematoma

Objectives. The purpose of this study was to evaluate the diagnostic accuracy of biplane and multiplane transesophageal echocardiography in patients with suspected aortic dissection, including intramural hematoma.Background. Transesophageal echocardiography is a useful technique for rapid bedside evaluation of patients with suspected acute aortic dissection. The sensitivity of transesophageal echocardiography is high, but the diagnostic accuracy of biplane and multiplane transesophageal echocardiography for dissection and intramural hematoma is less well defined.Methods. We studied 112 consecutive patients at a major referral center who had undergone biplane or multiplane transesophageal echocardiography to identify aortic dissection. The presence, absence and type of aortic dissection (type A or B, typical dissection or intramural hematoma) were confirmed by operation or autopsy in 60 patients and by other imaging techniques in all. The accuracy of transesophageal echocardiography for ancillary findings of aortic dissection (intimal flap, fenestration and thrombosis) was assessed in the 60 patients with available surgical data.Results. Of the 112 patients, aortic dissection was present in 49 (44%); 10 of these had intramural hematom (5 with and 5 without involvement of the ascending aorta). Of the remaining 63 patients without dissection, 33 (29%) had aortic aneurysm and 30 (27%) had neither dissection nor aneurysm. The overall sensitivity and specificity of transesophageal echocardiography for the presence of dissection were 98% and 95%, respectively. The specificity for type A and type B dissection was 97% and 99%, respectively. The sensitivity and specificity for intramural hematoma was 90% and 99%, respectively. The accuracy of transesophageal echocardiography for diagnosis of acute significant aortic regurgitation and pericardial tamponade was 100%.Conclusions. Biplane and multiplane transesophageal echocardiography are highly accurate for prospective identification of the presence and site of aortic dissection, its ancillary findings and major complications in a large series of patients with varied aortic pathology, Intramural hematoma carries a high complication rate and should be treated identically with aortic dissection.     

Electrocardiographic responses to atrial pacing and multistage treadmill exercise testing. Correlation with coronary arteriography

Atrial pacing was compared with multistage treadmill exercise testing in 50 patients undergoing diagnostic cardiac catheterization to determine the diagnostic sensitivity of atrial pacing. Coronary artery disease was considered significant if luminal narrowing greater than 75 percent was present. Twenty-one subjects (Group I) had no significant coronary artery disease with vessel narrowing of less than 50 percent. Twelve (Group II) had single vessel disease and 17 (Group III) had disease of two or more vessels.The mean maximal heart rate during atrial pacing was 140/min and during exercise testing was 131/min. A positive atrial pacing test result was obtained in 5 percent of patients in Group I, 17 percent of patients in Group II and 24 percent of patients in Group III. A positive multistage treadmill exercise test result was obtained in 10 percent of patients in Group I, 67 percent of patients in Group II and 94 percent of patients in Group III. These differences are statistically significant (P < 0.001). The sensitivity of atrial pacing was 20 percent compared with 83 percent for multistage treadmill exercise testing. The specificity of atrial pacing was 95 percent compared with 90 percent for multistage treadmill exercise testing. Thus, atrial pacing is an insensitive test in the diagnosis of ischemic heart disease and does not improve the diagnostic value of multistage treadmill exercise testing.     

Quantitative evaluation of cineaortography in the assessment of aortic regurgitation

Cineaortography, quantitative biplane left ventricular angiocardiography and Fick cardiac output studies were performed in 69 patients with aortic regurgitation to evaluate the usefulness of the aortogram in quantitating regurgitation. Thirteen patients had coexistent aortic stenosis and 12 had coexistent mitral stenosis. Patients with concomitant mitral regurgitation were excluded because their aortic regurgitant flow cannot be separately quantified with biplane ventriculography. Twenty-eight other patients without valvular regurgitation were also studied to assess further the accuracy of the quantitative ventriculography, and the stroke volumes derived from Fick and angiographic methods were found to correlate well (r = 0.97). Aortic regurgitation in the 69 patients, graded on a 1 to 5 scale from the aortogram, correlated significantly with the percent and volume of regurgitation (r = 0.56 and 0.65, P < 0.01), respectively). However, there was a wide range in amount of regurgitant flow within the aortographic grades, especially in grades 4 and 5, and there was considerable overlap between the grades. The degree of aortic regurgitation was more commonly overestimated than underestimated from the aortogram, but the correlation tended to be better in the patients with a large end-diastolic volume and normal ejection fraction and without aortic or mitral stenosis.     

Diagnosis and quantification of aortic stenosis with pulsed doppler echocardiography

The presence of disturbed or turbulent flow in the ascending aorta, as assessed with pulsed Doppler echocardiography, was correlated with the presence and severity of aortic stenosis in 95 patients: 18 normal subjects, 18 with a normal aortic prosthesis and 59 with clinically suspected aortic stenosis who underwent hemodynamic studies. Turbulence was defined as a frequency dispersion greater than 1.5 cm on a time interval histographic recording of the Doppler signal. Systolic turbulence was absent in all 18 normal subjects and present in the 59 patients with aortic stenosis. The patients were divided into a test group (Group I, 34 patients) and a prospective group (Group II, 25 patients). Five graphic indexes were evaluated indicative of either duration or amplitude of turbulence, amount of frequency dispersion above and below the 0 frequency shift baseline or degree of distortion of the “flow-curve” pattern of the analog signal. Chi square analysis of results in group I indicated significant (p < 0.001) differences in the magnitude of each index between patients with an aortic valve area greater than 1.0 cm² (n = 12) and those with an area less than 1.0 cm² (n = 22). When all five indexes were combined, 91 percent of patients with a valve area of less than 1.0 cm² had three or more indexes suggesting reduced valve area (positive score of 3 to 5), whereas 92 percent of patients with an area greater than 1.0 cm² had two or fewer positive indexes (p < 0.001). In Group II, 93 percent of patients with an aortic valve area of less than 1.0 cm² (n = 14) had a positive score of 3 to 5 whereas 82 percent of patients with an area greater than 1.0 cm² (n = 11) had a score of 0 to 2 (p < 0.001).The overall sensitivity of the technique (n = 59) in detecting valve areas of less than 1.0 cm² was 92 percent with a specificity of 87 percent; the predictive values for distinguishing areas less than from those greater than 1.0 cm² were 92 and 87 percent, respectively. The technique could not be used to distinguish patients with a valve area of 0.7 cm² or less (n = 27) from those with an area greater than 0.7 but less than 1.0 cm² (n = 9). Turbulence was either absent or mild (0 to 2 positive scores) in the patients with an aortic prosthesis. The presence of either aortic insufficiency (n = 17), increased age (65 years or older) (n = 20) or left ventricular dilatation or failure (n = 23) did not appear to alter the results significantly. Severity of aortic stenosis could not be assessed with M mode echocardiography in 30 of 59 patients (51 percent).Thus, pulsed Doppler echocardiography allows objective assessment of severity of aortic stenosis and may therefore be an excellent screening technique for detection of patients with an aortic valve area of less than 1.0 cm².     

Rapid diagnosis and management of thoracic aortic dissection and intramural haematoma: a prospective study of advantages of multiplane vs. biplane transoesophageal echocardiography.

AIMS: The purposes of this study were to compare the accuracy of multiplane vs. biplane transoesophageal echocardiography (TEE) in the diagnosis of aortic dissection and aortic intramural haematoma, and to test whether these techniques provide all the diagnostic information required to make management decisions. METHODS AND RESULTS: Fifty-eight consecutive patients with clinically suspected aortic dissection were studied with multiplane TEE; all cases who required surgery underwent intraoperative monitoring with multiplane TEE. The following multiplane TEE data were analysed: the angle between current and 0 degrees plane at which each view was obtained; the success rate in the evaluation of true and false lumen, entry tear, coronary artery involvement, aortic regurgitation, pericardial effusion. Advantages of multiplane over biplane TEE have been evaluated by the demonstration of usefulness of views obtained in planes other than 0 degrees-20 degrees or 70 degrees-110 degrees, assuming that with manipulation of a biplane probe a 20 degrees arc could be added to the conventional horizontal and vertical planes. On the basis of TEE findings, aortic dissection was confirmed in 36 cases (18 type A, 12 type B, six intramural haematoma). The specificity and sensitivity of TEE in terms of the presence or absence of aortic dissection or intramural haematoma were 100%. An additional clinical value of multiplane over biplane TEE in the evaluation of ascending aorta, aortic arch, entry tears and coronary artery involvement was demonstrated. All cases with type A aortic dissection or intramural haematoma involving the ascending aorta had an operation that was performed immediately after the diagnosis (hospital mortality, 13%). Patients with type B aortic dissection were treated medically; 25% of these cases were operated later (hospital mortality, 0%). CONCLUSIONS: Multiplane and biplane TEE have excellent and similar accuracies in the evaluation of aortic dissection and intramural haematoma. Multiplane TEE improves the visualization of coronary arteries, aortic arch and entry tears; it appears to be an ideal method as the sole diagnostic approach before surgery in type A aortic dissection.     

Chronically decreased aortic distensibility causes deterioration of coronary perfusion during increased left ventricular contraction

Objectives. This study investigated the long-term effects of decreased aortic distensibility on the heart in relation to coronary perfusion.Background.Aortic distensibility is decreased in patients with atherosclerosis and hypertension and in the elderly. However, the effect of a long-term decrease in aortic distensibility on coronary perfusion has not been fully investigated.Methods. Twelve anesthetized dogs underwent thoracotomy and were allocated to two groups: Group I included six control dogs with a normal aorta; Group II included six dogs with decreased aortic distensibility produced by banding the descending aorta. After 4 to 6 weeks, the dogs had a second operation to measure coronary artery flow and transmural flow distribution. Because the effect of decreased aortic distensibility on coronary perfusion may be affected by ventricular contractility, measurements were performed at baseline and during increased ventricular contraction induced by isoproterenol infusion.Results. At baseline, arterial compliance was reduced by 35% in Group II, but there was no change in total mean arterial resistance. Hemodynamic variables, regional wall motion and coronary flow were also similar in both groups. However, during isoproterenol infusion, coronary flow increased more in Group II than in Group I (p < 0.01), and the coronary flow reserve ratio (maximal peak hyperemic flow divided by rest flow) decreased more in Group II thin in Group I (mean [±SD] 1.9 ± 0.4 vs. 2.4 ± 0.3, p < 0.05). Moreover, although the transmural flow distribution was similar in the two groups at baseline, during isopraterenol infusion the endocardial flow increased less in Group II than in Group I (p < 0.05), and the endocardial/epicardial flow ratio was significantly decreased in Group II compared with Group I (mean [±SD] 0.70 ± 0.18 vs. 0.99 ± 0.22, p < 0.05). The subendocardial electrocardiogram showed ST segment elevation during isoproterenol infusion in Group II (p < 0.05) but not in Group I.Conclusions. These results demonstrate that during increased ventricular contraction, chronically decreased aortic distensibility contributes to a further decrease in the coronary flow reserve ratio, impairs endocardial blood flow and may induce subendocardial ischemia even in the absence of coronary artery stenosis.     

Progression of isolated aortic stenosis: Analysis of 29 patients having more than 1 cardiac catheterization

Factors related to progression of nonrheumatic aortic stenosis (AS) were analyzed in 29 adult patients who underwent serial hemodynamic studies over a mean of 71 months. AS was congenital in 8 patients and degenerative in 21. The patients were divided into 2 groups on the basis of the change in aortic valve area between the 2 studies. Twelve patients had a ≥ 25% reduction in aortic valve area (Group I) and 17 patients had < 25% decrease in aortic valve area (Group II). There were no significant differences between the 2 groups in age, interval between studies, cardiac output, left ventricular end-diastolic pressure, left ventricular peak systolic pressure and origin of AS (congenital or degenerative). Group I patients had significantly larger initial aortic valve areas than did Group II patients (1.3 ± 0.9 cm² versus 0.8 ± 0.4 cm², p = 0.02). Also, the initial peak transaortic pressure gradients were lower in Group I than in Group II (27 ±19 versus 58 ± 38 mm Hg, p = 0.01). Group I patients had a significantly greater increase in pressure gradient and a greater reduction in cardiac output than did Group II patients (24 ± 21 mm Hg in Group I versus?0.1 ± 24.5 mm Hg in Group II, p = 0.01, and ?1.0 ± 1.3 liters/min in Group I versus 0.10 ± 1.4 liters/min in Group II, p = 0.03). Thus, AS progressed in 41 % of a selected group of patients who underwent repeated cardiac catheterization. The progression was not predictable. Although 10 patients (34%) had moderate aortic regurgitation (AR) in the second study, it was not related to the origin or rate of progression of AS. Mild AS tends to progress more than severe AS. Congenital AS appears to progress at the same rate as degenerative AS.     

Aortic isthmus stenoses--dilatation in adulthood. A German cooperative study

An analysis of percutaneous transluminal angioplasty of the coarctation of the aorta in adults was evaluated in a cooperative study of the German Working Group of Angioplasty of the German Society of Cardiology. Dilation was performed in 18 patients with a mean age of 26 years (14-49 years). The success rate (gradient less than or equal to 20 mm Hg) was 78% regarding peak to peak gradient, 89% regarding mean gradient. The peak-to-peak gradient decreased from 82 +/- 16 mm Hg to 18 +/- 11 mm Hg. The diameter of the aortic isthmus increased from 0.7 +/- 0.3 cm to 1.3 +/- 0.4 cm (p less than 0.01). After six months only one restenosis occurred. The peak-to-peak gradient measured 10 +/- 12 mm Hg, the diameter 1.4 +/- 0.5 cm. In two patients a balloon rupture occurred without rupture-related complications. No patients died, no cross paralysis or aortic rupture occurred. In three of seven patients with trans-esophageal echocardiographic monitoring a small intimal flap was found; in one patient a media dissection occurred leading to a 15-min period of chest pain and spontaneous healing. In another patient successful dilation was controlled by acute control aortography and computer tomography. After discharge severe chest pain developed. A subtraction angiography of the aorta was negative. Six months later a biplane aortography of the distal thoracic aorta confirmed the diagnosis of aortic dissection type III DeBakey, previously diagnosed by transesophageal echocardiography.(ABSTRACT TRUNCATED AT 250 WORDS)     

Peak systolic blood pressure/end-systolic volume ratio: Assessment at rest and during exercise in normal subjects and patients with coronary heart disease

To assess the utility of a recently proposed index of left ventricular performance, the ratio of peak left ventricular systolic pressure to end-systolic volume, equilibrium radionuclide angiography was used to determine end-systolic volume and the systolic blood pressure obtained by cuff sphygmomanometer to determine peak systolic pressure. Data were analyzed at rest and during supine bicycle exercise in 15 normal subjects (Group 1), 50 patients with coronary artery disease (Group II) and 9 patients with obstructive lung disease and no evidence of coronary artery disease on clinical examination including exercise thallium imaging (Group III). In 15 subjects the correlation between the resting angiographic and radionuclide pressure/volume ratio was excellent (r = 0.929, p <0.005).Forty-seven (94 percent) of the 50 patients in Group II had a depressed pressure/volume ratio at rest or an abnormal change in this ratio during exercise, whereas only 43 (86 percent) of this group had an abnormal ejection fraction at rest or during exercise. Additionally, 3 of 15 subjects in Group I had an abnormal ejection fraction response, defined as less than 0.05 ejection fraction unit increase with exercise (specificity 80 percent), whereas all subjects in Group I had a normal increase in pressure/volume ratio (specificity 100 percent). At rest, neither index identified more patients with coronary artery disease than the other. Of the nine patients in Group III, six had an abnormal ejection fraction response to exercise, whereas only one had an abnormal pressure/volume ratio response.It is concluded that the end-systolic pressure/volume ratio is a useful index of left ventricular performance. In some patients during supine exercise stress it may be more sensitive than the ejection fraction response alone in identifying the presence of coronary artery disease.