Función diastólica del ventrículo izquierdo en pacientes con aneurisma apical post-infarto agudo de miocardio de cara anterior / Diastolic function of the left ventricle in patients with apical aneurysm after acute anterior wall myocardial infarction

Con el fin de evaluar cambios secuenciales en la función ventricular sistólica mediante la fracción de ejección (FE) y de la función ventricular diastólica a través del pico de llenado rápido (PLLR) (normal > 2,50 CFD/seg), se estudiaron 17 pacientes (pts) con infarto agudo de miocardio de cara anterior con un estetoscopio nuclear. Utilizando el Radiocardiograma Isotópico con cuatro diferentes posiciones se dividió a los pts en 2 grupos (G): Aquellos con aneurisma ventricular (5 pts) (G1) y los que tan sólo presentaban anormalidades de contracción segmentaria (12 pts) (g2). Todos los estudios fueron realizados en pts sin infarto previo, dentro de las 48 horas de iniciado el dolor y repetidos nuevamente antes del alta hospitalaria. La FE del G1 fue de 38ñ12% y de 37ñ12% en el 1§ y 2§ estudios respectivamente (p:NS). El PLLR del G1 fue de 2,79ñ0,72 CFD/seg en el 1er estudio y del 1,90ñ0,72 CFD/seg en el 2§ (p < 0,05). En el G2 fue de 1,87ñ0,61 CFD/seg y de 2,08ñ0,88 CFD/seg, sucesivamente (p:NS). La diferencia entre G1 y G2 durante el 1er estudio fue significativa (p < 0,05). Por lo tanto, los ventrículos aneurismáticos presentaron una función ventricular diastólica más cercana a la normal durante las primeras horas del infarto, disminuyendo ésta durante el período de convalescencia, a pesar de no haber habido cambios en la FE. Los pacientes sin aneurisma ventricular no presentaron cambios significativos

Función diastólica del ventrículo izquierdo en pacientes con aneurisma apical post-infarto agudo de miocardio de cara anterior / Diastolic function of the left ventricle in patients with apical aneurysm after acute anterior wall myocardial infarction

Con el fin de evaluar cambios secuenciales en la función ventricular sistólica mediante la fracción de ejección (FE) y de la función ventricular diastólica a través del pico de llenado rápido (PLLR) (normal > 2,50 CFD/seg), se estudiaron 17 pacientes (pts) con infarto agudo de miocardio de cara anterior con un estetoscopio nuclear. Utilizando el Radiocardiograma Isotópico con cuatro diferentes posiciones se dividió a los pts en 2 grupos (G): Aquellos con aneurisma ventricular (5 pts) (G1) y los que tan sólo presentaban anormalidades de contracción segmentaria (12 pts) (g2). Todos los estudios fueron realizados en pts sin infarto previo, dentro de las 48 horas de iniciado el dolor y repetidos nuevamente antes del alta hospitalaria. La FE del G1 fue de 38ñ12% y de 37ñ12% en el 1º y 2º estudios respectivamente (p:NS). El PLLR del G1 fue de 2,79ñ0,72 CFD/seg en el 1er estudio y del 1,90ñ0,72 CFD/seg en el 2º (p < 0,05). En el G2 fue de 1,87ñ0,61 CFD/seg y de 2,08ñ0,88 CFD/seg, sucesivamente (p:NS). La diferencia entre G1 y G2 durante el 1er estudio fue significativa (p < 0,05). Por lo tanto, los ventrículos aneurismáticos presentaron una función ventricular diastólica más cercana a la normal durante las primeras horas del infarto, disminuyendo ésta durante el período de convalescencia, a pesar de no haber habido cambios en la FE. Los pacientes sin aneurisma ventricular no presentaron cambios significativos (AU)

Isolated right atrial tamponade by serous fluid simulating tricuspid stenosis.

Echocardiography is a key diagnostic tool in the recognition of pericardial tamponade. A 56-year-old man in whom severe dyspnea developed 22 days after cardiac surgery is described. Echocardiography suggested tricuspid valve disease but showed no pericardial abnormalities. Catheterization revealed functional stenosis of a normal tricuspid valve caused by loculated serous pericardial fluid.

The limited spectrum of patients studied in exercise test research. Analyzing the tip of the iceberg.

To investigate reasons for the wide variation in formal studies of sensitivity and specificity indexes for the diagnostic efficacy of the graded exercise test for angiographically defined coronary disease, data were collected on 205 consecutive exercise tests at two hospital-based exercise laboratories. For calculations of sensitivity and specificity, stress test data are usually analyzed with many exclusions for ineligibility, with equivocal results omitted, and only in patients undergoing angiography. Consequently, only 3% of patients who received the tests in this survey would have been included in a typical formal study of diagnostic efficacy. In the same way that the visible tip of an iceberg misrepresents its extent and depth, the patients assembled in studies of diagnostic tests may be a highly selected group that misrepresents the intended population.

The multicentric character of normal left ventricular wall motion. Implications for the evaluation of regional wall motion abnormalities by contrast angiography.

Current radiologic approaches to evaluation of regional ventricular wall motion generally employ rectilinear hemichords ("hemiaxes") or radial hemichords ("chords"), defined by the presumptions that wall segments move either perpendicularly toward the ventricular long axis, or toward some common center, respectively. In order to test these presumptions, the end-systolic and end-diastolic frames of 17 normal right anterior oblique (left) ventriculograms were analyzed, using a digitizer and a computer. The motion vectors of 47 points on each ventriculographic perimeter were defined by centers (located along the ventricular long axis). Twenty average centers were found which could be represented by three centers, for six regions of the normal angiographic silhouette. Computer models of abnormal regional wall motion, using three centers, disclosed appreciable discrepancies among the chord, hemiaxis and rectilinear area methods, particularly for the apical and basal wall regions. The model data suggest that the wall region, itself, dictates the center which should be used for measuring an abnormality of regional wall motion.

Dysfunction and thromboembolism associated with cardiac valve xenografts in adults.

Cardiac valve xenografts often fail relatively early in children. We analyzed the incidence of valve dysfunction and thromboembolism in 253 consecutive adult survivors who received 294 porcine xenograft valves (150 aortic, 125 mitral and 19 tricuspid) from June 1974 to December 1979 (41% of all adult valve replacements). Mean follow-up was 25.6 months (range 9-75 months). Valve dysfunction occurred in four of 294 xenografts (three in mitral position and one in tricuspid position), all four caused by recurrent endocarditis; these four patients survived reoperation and are doing well. Thromboembolism occurred in six of 294 xenografts, none in aortic or tricuspid positions of rhythm or anticoagulation. Four of the six mitral xenografts associated with thromboembolism were in the 16 patients who had atrial fibrillation and received aspirin and dipyridamole but no warfarin (12% per patient-year), and two were in the 14 patients who were in sinus rhythm and were not taking medication, one of whom had recurrent Candida endocarditis. No thromboembolism occurred in mitral xenografts with sinus rhythm and antiplatelet agents. Thromboembolism did not occur in patients who were in atrial fibrillation and receiving warfarin anticoagulation. Late death (30 of 253) was unrelated to valve dysfunction, and only one death resulted from thromboembolism. This study showed excellent xenograft performance for as long as 75 months. Valve dysfunction occurred only with recurrent endocarditis, and thromboembolism occurred after mitral replacement, especially in patients who were in atrial fibrillation and were not receiving anticoagulants.

Multigated equilibrium radionuclide angiocardiography: improved detection of left ventricular wall motion abnormalities and aneurysms by the addition of the left lateral view.

The usefulness of adding the left lateral (LLAT) view to the standard anterior and left anterior oblique views in multigated equilibrium radionuclide angiocardiography was assessed in 50 patients. Contrast ventriculography was used as the standard. Receiver operating characteristic (ROC) curve analysis was used to assess results. Recognition of inferior wall motion abnormality and left ventricular aneurysms was improved significantly by the addition of the LLAT view. Sensitivity was improved for inferior wall motion abnormality and for aneurysms; there was no loss of specificity. There was no improvement in recognition of anterior wall and apical regional abnormalities in the absence of aneurysms.

Predictive accuracy of coronary artery calcification and abnormal exercise test for coronary artery disease in asymptomatic men.

To determine the predictive accuracy of fluoroscopically detected coronary artery calcification (CAC) and a positive submaximal exercise test, 129 asymptomatic men were screened; 13 had both coronary artery calcification and positive exercise test (greater than or equal to 1.0 mm ST-segment depression). These 13 men were studied at coronary arteriography. They had a mean age of 44 years (range 41-56 years); none had history or symptoms of heat disease and all had normal resting ECGs at entry. CAC was detected in one artery in 10 men, in two arteries in two men, and in three arteries in one man. Coronary artery disease (CAD) was considered clinically significant if any major coronary branch was narrowed > 50%. Coronary arteriography revealed 12 men with clinically significant CAD (one-vessel CAD in four, two-vessel CAD in five and three-vessel CAD in three men) and one man with minor one-vessel CAD. The predictive accuracy was 100% for minor CAD and 92% for clinically significant CAD. The location of CAC and CAD correlated, but the absence of CAC did not rule out the presence of CAD at coronary arteriography. Furthermore, CAC did not indicate the location of the highest stenotic (most occlusive) lesions seen at arteriography. Follow-up for the 13 patients was 36 months; three patients developed typical angina and one patient developed a transmural myocardial infarction. This study suggests that the predictive accuracy of CAC and a positive exercise test in the middle-aged non-hyperlipidemic asymptomatic male is very high (100% for CAD and 92% for clinically significant CAD) and that CAC and a positive exercise test predict an early appearance of angina or myocardial infarction in previously asymptomatic men.

Genesis of pericardial knock in constrictive pericarditis.

A pericardial knock is a common finding in constrictive pericarditis. However, its origin has been uncertain. One hypothesis suggests that it is due to sudden deceleration of ventricular filling. To validate this hypothesis, left ventriculograms, phonocardiograms and external pulse recordings were obtained in seven patients with hemodynamic and pathologic findings of constrictive pericarditis and in seven normal subjects. Left ventriculographic silhouettes were digitized and left ventricular volumes were calculated by computer at 16 ms intervals. Curves of left ventricular volume versus diastolic filling time were constructed for each patient. Pericardial knock was recognized as an early high frequency sound recorded between 90 to 120 ms after the aortic closing sound and occurring at the trough of the Y descent of the jugular venous pressure tracing. The timing of the pericardial knock in five patients with constrictive pericarditis corresponded to a sudden and premature plateau of the diastolic left ventricular volume curve representing 85 +/- 4 percent (mean +/- standard deviation) of ventricular filling. The diastolic plateau was missing in two patients with constrictive pericarditis who had no pericardial knock. In these cases, the rate of ventricular filling was faster than normal in the first 20 percent of diastole. Thus, this study related pericardial knock to an abrupt plateau inthe diastolic left ventricular volume curve, supporting the view that sudden cessatin of ventricular filling generates the pericardial knock of constrictive pericarditis. Two mechanisms are proposed by which the filling plateau may produce the knock, and it is postulated that both ventricles may participate in the knock phenomenon.

Is cocaine a sympathetic stimulant during general anesthesia?

Eighteen patients undergoing coronary artery surgery were observed to examine whether cocaine in a clinically used dose exerts sympathomimetic effects during general anesthesia. Eleven patients received cocaine hydrochloride as a 10% solution (1.5 mg/kg) applied topically to the nasal mucosa before nasotracheal intubation. Seven patients had a similar procedure without cocaine. Blood pressure, pulse rate, cardiac index, left ventricular stroke work index, total peripheral vascular resistance, and pulmonary vascular resistance were measured. There were no important differences in cardiovascular function between patient groups. The rapid rise in plasma cocaine concentration, reaching 331 ng/mL at 30 minutes and 320 ng/mL at 45 minutes, bore no apparent relationship to any changes in cardiovascular function. We conclude that under conditions of this study, administration of topical cocaine does not exert any clinically significant sympathomimetic effect and appears to be well tolerated in anesthetized patients with coronary artery disease.

Bypass surgery for left main coronary artery disease. Reduced perioperative myocardial infarction with preoperative intra-aortic balloon counterpulsation.

From July 1975 to December 1977, 91 consecutive patients with left main coronary artery disease defined by cardiac catheterisation as greater than or equal to 50 per cent luminal narrowing underwent coronary bypass surgery. Prospective examination of the preoperative and postoperative clinical course of these patients was performed to determine the incidence of perioperative myocardial infarction. Intra-aortic balloon counterpulsation was instituted preoperatively in 35 patients, and these patients were classed as group A. Fifty-six patients did not receive the intra-aortic balloon pump and were classed as group B. Of 26 demographic, clinical, haemodynamic, and operative descriptors, only two were found to be significantly different between the two groups: the severity and the pattern of angina. Group A had a higher percentage of patients with class IV angina (80% vs 45%) and a greater proportion with unstable angina (37% vs 7%). Despite these differences group A patients had only a 3 per cent incidence of perioperative myocardial infraction while group B had a 23 per cent perioperative infarction rate. It is suggested that perioperative intra-aortic balloon counterpulsation can reduce the risk of perioperative myocardial infraction in patients with left main coronary artery stenosis.

The angiographic appearance of the coronary arteries in constrictive pericarditis.

Coronary artery motion was evaluated in normal subjects and patients with constrictive pericarditis (CP), congestive cardiomyopathy, restrictive cardiomyopathy, and coronary artery disease. Seven of the 8 patients with CP had lack of motion of the major coronary arteries. Nine of the 10 patients with congestive cardiomyopathy and a markedly reduced ejection fraction showed normal motion, as did all 4 with restrictive cardiomyopathy and 9 of the 10 with segmental dysfunction due to coronary disease. Pericardial stripping in 5 patients with CP revealed epicardial involvement corresponding to regions of absent motion; one CP patient with normal motion had no epicardial involvement. Lack of motion may suggest CP when the diagnosis is unsuspected, right heart pressures are not obtained, or hemodynamics are atypical. This sign may also help to distinguish CP from restrictive cardiomyopathy, which produces similar hemodynamics.

Multiple gated cardiac blood pool imaging for left ventricular ejection fraction: validation of the technique and assessment of variability.

The intrinsic variability and accuracy of left ventricular ejection fraction determined by multiple gated cardiac blood pool imaging was evaluated in 83 patients. Ejection fraction by gated studies correlated well with data from first pass radionuclide angiocardiography (r = 0.94) and from contrast angiography (r = 0.84). Intra- and interobserver variabilities of absolute ejection fraction were minimal (mean +/- standard deviation 1.4 +/- 1.2 and 1.6 +/- 1.5 percent, respectively) and were not different for normal (ejection fraction 55 percent or greater) and abnormal patients. Ejection fraction was determined twice in 70 patients: on the same day at intervals separated by 1 to 2 hours (41 patients) and on 2 different days (29 patients). Ejection fraction ranged from 18 to 91 percent and was normal in 37 patients. There was no difference in mean serial variabilities of absolute ejection fraction for all repeat studies performed on the same and separate days (3.3 +/- 3.1 versus 4.3 +/- 3.1 percent (not significantly different). The mean variability of absolute ejection fraction for repeat studies in normal patients was significantly greater than in abnormal patients (5.4 +/- 4.4 versus 2.1 +/- 2.0 percent, P less than 0.01). The incidence rate of absolute interstudy changes of 5 percent or more was significantly higher in normal than in abnormal patients (P less than 0.01). This differential variability should be considered in interpreting sequential changes in left ventricular ejection fraction. To be attributed to nonrandom physiologic alterations, the absolute change in ejection fraction should be 10 percent or more in normal patients and 5 percent or more in abnormal patients.