The vectorcardiogram as an aid to diagnosis in left ventricular-right atrial communication

Frank vectorcardiograms (VCGs) in four patients with left ventricular-right atrial (LV-RA) communication were analyzed and compared with published values of VCGs of normal individuals and those from a group of patients with membranous ventricular septal defect. It was observed that the QRS-loops in the frontal and sagittal planes of the patients with LV-RA communication are shifted more superiorly than usual. Thus, almost 50% of the QRS-loop area was superior to the X- and Z-coordinates in the frontal and sagittal planes, whereas in the controls less than 10% of the frontal and sagittal plane QRS-loops were superior to the horizontal axes. The QRS-loops of patients with LV-RA communication thus seem to be halfway between normal and endocardial cushion defect loops. An unusual degree of superior orientation of the QRS-loop in a patient with clinical findings of a ventricular septal defect should arouse suspicion of a LV-RA communication. Also in patients with an isolated ventricular septal defect but with an exaggerated superior orientation of the QRS-loop in the frontal and sagittal planes, the interatrial septum should be examined at the time of operation to exclude the possibility of an associated LV-RA communication.     

Mitral valve echoes in patients with mitral valve prolapse syndrome.

Echocardiology is an important tool in diagnosing patients with the mitral valve prolapse (MVP) syndrome. An unusual echocardiographic finding reported in this study was observed in 12 of 83 patients (14.5 per cent) with MVP syndrome. The finding consisted of a pattern of multiple, high-intensity parallel echoes behind the anterior mitral leaflet noted throughout diastole which in character were closely akin to those previously observed in left atrial myxoma or hemodynamically significant flail mitral valve leaflet. These latter diagnoses were excluded by other criteria. The prevalence of this finding in patients with MVP was significantly increased (P < .01 by Chi-square contingency testing) when contrasted with 44 patients without MVP. There was no identifying feature in the clinical history or physical examination which could be used to predict those in whom the diastolic echoes were observed. However, a significant increase in dysrhythmias as recorded by routine electrocardiogram or 24-hour Holter monitoring was noted. Angiographic information obtained in selected patients suggested that the posterior leaflet per se caused these diastolic echoes. Because of patulous transformation of the valve, elongation of the chordae, or loss of support of the papillary muscle from the posterior free wall, the posterior leaflet appeared drawn forward toward the anterior leaflet, perhaps from a venturi-like effect caused by the rapid ingress of blood during diastolic filling. This malpositioning of the posterior leaflet was not associated with significant mitral regurgitation and appears to represent but another facet in the spectrum of mitral valve prolapse.     

Spontaneous return of sinus rhythm in older patients with chronic atrial fibrillation and rheumatic mitral valve disease. Description of three patients

Three patients with rheumatic mitral stenosis had had atrial fibrillation for over ten years before spontaneously restoring normal sinus rhythm. Each had undergone a closed mitral commissurotomy ten to twelve years before the conversion. Their ages at the time of resuming normal rhythm were 47, 59, and 71 years. This unusual phenomenon has no satisfactory explanation by our present knowledge of the natural history of mitral valve disease and the pathogenesis of atrial fibrillation.     

Refractory ventricular arrhythmias in a patient with mitral valve prolapse. Successful control with mitral valve replacement

A 35-year-old woman with proven mitral valve prolapse developed life threatening ventricular arrhythmias which were refractory to medical therapy. She had one episode of "cardiac arrest" presumably due to ventricular tachycardia or possibly ventricular fibrillation, and was successfully resuscitated with closed chest compression. Mitral valve replacement resulted in dramatic control of the ventricular arrhythmias. Over a period of three years following the operation, she has been able to resume an active life with occasional ventricular premature beats and no further episodes of ventricular tachyarrhythmias.     

Abnormal motion of the mitral valve with pericardial effusion: Pseudo-prolapse of the mitral valve.

The echocardiograms of seven patients with large pericardial effusions were found to show posterior motion of the mitral leaflets in systole as seen in prolapse of the mitral valve. Repeat echocardiograms after resolution of the effusion revealed normal mitral valve motion. None of the patients had clinical evidence of prolapsed mitral valve. We postulate that a posterior swing of the heart within the pericardial fluid occurring in late systole causes posterior displacement of the mitral valve simulating a prolapsed valve.     

Metabolic and cardiovascular abnormalities in patients with peripheral arterial disease

Twenty-eight consecutive patients of an average age of 63 years with intermittent claudication secondary to underlying peripheral arterial disease were studied for evidence of metabolic or other cardiovascular abnormalities and the results obtained were compared with those of 28 matched control subjects free of vascular disease. Patients with peripheral arterial disease had significantly higher levels of systolic and diastolic blood pressure, a greater incidence of ECG abnormalities, lipoprotein abnormalities, elevated serum triglycerides, and serum copper. The incidence of smoking and abnormal glucose tolerance, while higher in peripheral arterial disease patients, was not statistically significant. Hematocrit and serum cholesterol levels were nearly indentical in both groups of patients. Twenty-six of the 28 patiens with peripheral arterial disease had either a cardiovascular or a metabolic abnormality, indicating the high incidence of multisystem illness in this disorder. The epidemiologic data in peripheral arterial disease are similar to those in coronary artery disease but some measurements contrast sharply, such as the apparent normal level of serum cholesterol in patients with peripheral arterial diseases.     

Noninvasive assessment of myocardial function in young patients with mitral valve prolapse.

To evaluate myocardial function in patients with documented mitral valve prolapse (MVP) 14 patients (six men and eight women with a mean age of 28 +/- 6.3 years) were examined noninvasively. Systolic time intervals were recorded at rest (in the supine and upright position) and after bicycle ergometry (upright position) and were compared with 10 healthy control subjects of similar age. Tracings were coded with random numbers and were evaluated by two blinded investigators. Contractility indices such as pre-ejection period index (PEPc) and ratio pre-ejection period/left ventricular ejection time (PEP/LVET) revealed no significant differences between patients and controls both at rest and after exercise. We conclude that young patients with MVP have no evidence for impaired myocardial function, provided there is no significant mitral incompetence or associated heart disease.     

Relationship of pulmonary artery diastolic and pulmonary artery wedge pressures in mitral stenosis

Resting and exercise hemodynamic studies were performed in 33 patients with mitral stenosis (14 men and 19 women; average age, 25 years) in normal sinus rhythm with normal pulmonary vascular resistances. A normal pulmonary vascular resistance was assumed when the resting pressure gradient between the pulmonary artery diastolic and mean pulmonary artery wedge pressures was 5 mm. Hg or less. A satisfactory correlation existed between the pulmonary artery wedge and pulmonary artery diastolic pressures at rest (r = 0.9017) and during exercise (r = 0.8670). A method of predicting pulmonary artery wedge pressure from pulmonary artery diastolic pressure during exercise was formulated. The correlation between the predicted and measured exercise pulmonary artery wedge pressures was very close (r = 0.9561). It is suggested that during exercise the pulmonary artery diastolic pressure can be modified as above and substituted for mean pulmonary artery wedge pressure if the resting gradient between pulmonary artery wedge and pulmonary artery diastolic pressure is known.     

The relationship of pulmonary artery wedge pressure to the posterior aortic wall echocardiogram in patients free of obstructive mitral valve disease

Aortic wall echocardiograms were obtained simultaneously with pulmonary artery wedge pressures (PAWP) in 21 patients free of obstructive mitral valve disease. There was a significant (p < 0.001) negative correlation between the fraction of passive posterior aortic wall motion occurring in the first third of diastole (the atrial emptying index-AEI) and the pulmonary artery wedge pressure (r = ?0.91). The AEI for patients with normal PAWP (≤ 12mm. Hg) was 0.94 ± 0.06 (mean ± S.D.) compared with 0.61 ± 0.20 for those with abnormal PAWP (> 12 mm. Hg). No patient with a normal PAWP had an AEI < 0.80, and no patient with a PAWP > 18 mm. Hg had an AEI > 0.66. These data suggest that analogous to the reported use of the AEI to estimate severity of mitral obstruction, the index provides a noninvasive measure of left ventricular filling pressure when the mitral valve is normal.     

Site of origin of ventricular premature beats in patients with mitral valve prolapse

This study examines the site of origin and possible etiology of ventricular premature beats (VPB) in patients with mitral valve prolapse.Ten patients with mitral valve prolapse documented by echocardiogram form the study group. All patients had prolapse of the posterior leaflet and three additionally had anterior prolapse. There were eight females and two males, with a mean age of 29.1 ± 11.1 years. All patients were having unifocal VPBs at rest. A vectorcardiogram (VCG) was taken of the VPB by a technique which allowed all VCG loops to be written from the same beat.The VCG analysis indicated that the VPB forces were directed anteriorly, inferiorly, and to the left in six patients. In two patients the VPB was directed posteriorly, inferiorly, and to the left, consistent with right ventricular origin. One of these patients had episodes of ventricular tachycardia. One was anterior, superior, and to the left, and one was markedly anterior, superior, and to the right. In all patients the initial portion of the QRS was inscribed slowly. The three patients with additional anterior prolapse did not show a common difference from those with isolated posterior prolapse.It is concluded that: (1) The majority of these VPBs originate from the posteriorbasal portion of the left ventricle. (2) They originate in the myocardium and not in the Purkinje tissue. (3) There is no relationship between the location of prolapse and the VPB morphology.     

Correlation of heart size with clinical and hemodynamic findings in patients with coronary artery disease.

The clinical, hemodynamic, and angiographic findings were correlated with the heart size in 207 patients with proved coronary artery disease. Cardiomegaly was noted in 34 patients and normal heart size in 173. In these two groups, the patients' age range, duration of disease, and history of myocardial infarction were similar. There was no statistical difference in incidence of shortness of breath, hypertension, left ventricular hypertrophy, or abnormal glucose tolerance. Patients with cardiomegaly had a significantly higher incidence of congestive heart failure (26 per cent) as compared to patients with normal heart size (2.9 per cent) (P less than 0.001). Patients with enlarged heart presented a high incidence of anterior wall or multiple myocardial infarction (73 per cent) (P less than 0.001). The cardiomegaly group had a high incidence of elevated end-diastolic volumes, elevated end-diastolic pressures, and diminished ejection fractions when compared to patients with normal heart size (P less than 0.01). Double and triple coronary artery disease was more frequent in patients with cardiomegaly and total coronary score was also higher in this group (P less than 0.005). Asynergy was present in 55 per cent of patients with normal heart size but in 82 per cent of those with enlarged hearts (P less than 0.01). The group of patients with cardiomegaly and documented congestive heart failure had ejection fractions less than 0.30. Cardiac catheterization is probably not advisable in these patients in the absence of associated significant mitral regurgitation, ventricular septal defect, or ventricular aneurysm.     

Clinical and hemodynamic results after combined aortic and mitral valve replacement with the Lillehei-Kaster pivoting disc valve.

Combined mitral and aortic valve replacement with the Lillehei-Kaster pivoting disc valve prosthesis was performed in 23 patients. Hospital mortality rate was 8.3 per cent. Detailed postoperative clinical and hemodynamic studies were performed after a mean follow-up period of 24.4 months. Replacement of both valves had resulted in a marked symptomatic and hemodynamic improvement with a normal or nearly normal resting value of cardiac output, pulmonary arterial pressure, and pulmonary vascular resistance while left ventricular end-diastolic pressure (LVEDP) had increased significantly. The rise in left ventricular end-diastolic pressure most probably might be related to the simultaneous rise in cardiac output (Starling mechanism), reflecting the severity and irreversibility of the underlying myocardial disease. Most patients also had systolic gradient across the aortic prosthesis, as well as diastolic gradient across the mitral prosthesis. The gradients across the mitral prosthesis were approximately the same as seen after single valve replacement, while the pressure gradients across the aortic prosthesis were somewhat smaller than previously reported. Angiographic studies of the aortic valve movement indicated that the opening angle of the disc was approximately 60 degrees, and thus less than according to the valve specifications.     

Accurate internal correction for the magnification of cineangiocardiography in infants with congenital heart disease

Correction for x-ray magnification at cineangiocardiography (cine) requires accurate localization of the level of the left ventricle (LV). This study compared LV volumes calculated using a standard external reference object (area grid) with volumes calculated using an intracardiac radiopaque catheter balloon in cine studies of casts (n = 26), normal lambs (n = 15), and infants with congenital heart disease (n = 11). Comparisons of LV volumes calculated using both correction methods with true cast displacement volumes were excellent (r = 0.99). Correlations of both methods were highly significant (p less than 0.001) in casts (r = 0.99), normal lambs (r = 0.97), and in infants (r = 0.83). The absolute percent difference (17.6 +/- 2.4 SE%) between LV volumes calculated by both methods was greatest in infants. Thus external localization of the LV may be more difficult in infants. The radiopaque balloon provides convenient accurate correction for cine x-ray magnification and calculation of LV volumes, particularly since flow-directed catheters are widely used for diagnostic cine ventriculography in infants.     

Effects of induced psychological stress on click and rhythm in mitral valve prolapse

Our clinical observations suggested that anxiety accentuated the click in patients with mitral valve prolapse. In order to evaluate this systematically, a psychological stress was administered to 30 subjects-15 patients with click murmur syndrome and 15 normal controls. The phonocardiogram was recorded and the electrocardiogram were continuously monitored to assess the effects on arrhythmias.State Anxiety Inventory scores demonstrated an increase in anxiety during the psychological stress. A change in rhythm during psychological stress was noted in five of the 15 patients. No arrhythmias occurred in the control subjects during psychological stress (p < .025). Amplitude of the click increased during psychological stress in five of the 15 patients, in four associated with arrhythmia.The only patient with auscultatory-electrocardiographic variant developed frequent, multifocal ventricular ectopics with couplets during the psychological stress.Acute psychological stress exerts important effects on the rhythm and click only in some patients with mitral valve prolapse, and may provide a mechanism for intermittence of clicks and episodes of profound unexplained arrhythmias.     

Regional myocardial perfusion at rest and during intracoronary papaverine in patients with coronary artery disease

Regional myocardial perfusion was measured in 32 patients with the xenon-133 washout technique at rest and after 5 mg of intracoronary papaverine. Areas of decreased perfusion and/or decreased vasodilation were identified visually from computer-generated functional images. The locations of arteries and stenoses, obtained from identically positioned cineangiograms, were overlaid on the functional images. Perfusion rates for 62 myocardial regions were calculated and correlated with the percentage of stenosis. There was no association between degree of stenosis and perfusion at rest. Regional myocardial perfusion increased after papaverine in regions supplied by coronary arteries without stenoses (0% to 25%), 88.6 ± 4.7 ml/min/100 gm. This increase was significantly greater (p < 0.001) than the increase in regions supplied by 51% to 75% stenoses (23.7 ± 6.3 ml/min/100 gm), or 76% to 99% stenoses (12.9 ± 6.3 ml/min/100 gm), or 100% stenoses (2.5 ± 3.8 ml/min/100 gm). Thus there was an inverse relationship between the increase in myocardial perfusion stimulated by papaverine and the degree of coronary artery stenosis measured angiographically. In regions supplied by two stenoses in series, vasodilation produced less of an increase than a single stenosis of a similar degree.