False left ventricular aneurysm as a complication of open heart surgery

A false aneurysm developed at the site of left ventricular venting in an 8-year-old boy who had undergone aortic valve commissurotomy under cardiopulmonary bypass. The diagnosis was made by clinical examination and chest radiography and confirmed by left ventricular cineangiography. The aneurysm was successfully resected.

Long-term survival after isolated replacement of mitral valve with ball-valve prosthesis

In 111 patients whose diseases mitral valve was replaced with a ball-valve prosthesis the actuarial survival rate, including the hospital mortality of 10.8%, was 66% after 5 years and 59% after 8 years of follow-up. This suggests that in patients with moderate or severe symptoms due to mitral valve disease, replacing the valve can prolong life. However, in patients with no cardiac symptoms or with sinus rhythm and mild symptoms, it is doubtful that mitral valve replacement can prolong life, for the prognosis in these patients is favourable without operation.

Clinical echocardiography - an overview

Echocardiography is a new diagnostic technique for noninvasive assessment of the size, structure and function of the heart, using pulsed ultrasound. The physical principles underlying the generation of the ultrasonic signal for diagnostic use and the three modes (A, B and M) of displaying the reflected "echo" signal are briefly discussed. A full echographic study of the heart includes evaluation of the dimensions and patterns of movement of its various structures and chambers. The normal anatomic relations and echographic appearances of these structures and the changes they undergo in some of the more commonly recognized clinical conditions are described. Assessment of output and contractile behaviour of the left ventricle and recognition of various congenital heart defects are two of the more recent applications of this technique. Two-dimensional sector and multiscanning devices permit several areas of the heart to be visualized simultaneously in "real time".

Long-term survival after aortic valve replacement using Smeloff-Cutter prosthesis

The long-term prognosis of 187 consecutive patients who received single aortic valve replacement using Smeloff-Cutter prosthesis was studied. Of the 163 patients who survived the operation, a long-term follow-up (up to eight years) was obtained in 153 patients (95%). A total of 34 patients (22%) died during the follow-up period. Including the hospital mortality, the actuarial survival rate of our patients with Smeloff-Cutter prosthesis was 0.69 after the fifth year and 0.611 after the eighth year of follow-up. This is similar to the actuarial survival rate of patients with Starr-Edwards prosthesis but it appears significantly better than the expected survival rate of symptomatic patients with aortic stenosis treated without surgery. Thus, this result supports the contention that aortic valve surgery in properly selected patients can prolong life expectancy in addition to relieving symptoms in patients with aortic valve disease. The majority of surviving patients reported to have improved (88%) since the operation and to be symptom free (82%).

Ruptured aneurysms of sinuses of Valsalva

At least one additional cardiac lesion was present in 18 consecutive patients with ruptured aneurysms of the sinuses of Valsalva who were investigated between 1956 and 1973 at the University of Alberta Hospital. Clinical diagnosis was made in 78% (14/18) of the patients. Confirmation at cardiac catheterization, operation or autopsy was obtained in all but one. The main sites of rupture were the right ventricle (seven cases), right atrium (five) and left ventricle (five). Fifty percent (9/18) are alive and well following prompt operative repair, an average of 8.2 years later (range, six months to 15 years). Replacement of the aortic valve was associated with a high mortality (50% early, 13% late, total 63%) which could be explained by the higher operative risk in this group of very ill patients. Eight patients (44.4%) had had bacterial endocarditis prior to presentation and this may have played a significant role in the rupture of the sinus of Valsalva aneurysm.

Effects of nitroglycerin on left ventricular volumes and wall tension in patients with ischaemic heart disease

Since the dimensions of the ventricles are related to both myocardial tension and myocardial oxygen consumption (MVO2), the effects of nitroglycerin on the left ventricular volumes and left ventricular haemodynamics were studied in patients with ischaemic heart disease. The ventricular volumes were estimated using the constant infusion technique (indocyanine green) of Shaffer (1964). Sublingual administration of nitroglycerin (0.6 mg.) resulted in a significant reduction in cardiac output (27%), mean systolic pressure (21%), left ventricular end-diastolic pressure (63%), stroke volume (27%), left ventricular end-diastolic volume (26%), and left ventricular work (41%). Both calculated circumferential myocardial force (40%) and the myocardial tension (33%) decreased during systole, while the pressure-time index decreased by 27%. A similar decrease was also found in the contractile element work (42%), and mean circumferential fibre shortening rate (22%). Thus, this study has shown that the major determinants of MVO2, i.e. myocardial wall tension, the velocity of contraction, and contractile element work, decrease significantly after administration of nitroglycerin.

Hemodynamic changes following correction of severe aortic stenosis using the Cutter-Smeloff prosthesis

Twelve patients with pure or dominant stenosis were studied before and after aortic valve replacement (Cutter-Smeloff). The changes in cardiac output and A-V O2 difference were small and insignificant, but exercise stroke volume increased from 72 to 96 ml after the surgery. The aortic peak systolic gradient was 92 +/- 29 mm Hg before and 4 +/- 9.8 mm Hg after surgery. The PA wedge pressure, taken as a measure of the LV diastolic pressure, decreased from 18 mm Hg to 12 mm Hg at rest and 30 mm Hg to 16 mm Hg on exercise. The PA pressures also decreased from 37/18 (mean, 26) to 28/11 (17) mm Hg at rest, and 61/31 (43) to 41/17 (27) mm Hg on exercise, but the PA and PA wedge pressures maintained their tendency to increase in a linear manner with oxygen consumption (Vo2) on exercise after surgery. As a result of decreased wedge pressure, the pulmonary vascular resistance also decreased significantly afterward. The adequacy of cardiac output at rest and on exercise expressed by cardiac output as the linear function of Vo2 improved toward the normal (values before operation, CO = 2.78 + 0.0069 Vo2, r = 0.84; after operation, CO = 3.80 + 0.0062 Vo2, r = 0.91). The exercise factor (delta CO/delta Vo2) or the regression coefficient, however, was similar before and after surgery. The hemodynamic result was satisfactory although some abnormalities of the left ventricular function persisted after operation.

Malfunction of the mitral valve prosthesis (Cutter-Smeloff). Clinical and hemodynamic observations in three cases

Three cases of intermittent obstruction of the mitral prosthesis (Cutter-Smeloff) due to ball variance have been reported. The typical findings were marked variation in the arterial pulse and the intensity of the mitral closing sound and intermittent absence of the opening click. The phonocardiography revealed varying intervals from aortic closing sound to the opening click (A 2 - OC interval). Hemodynamic studies revealed fluctuating aortic and pulmonary artery wedge pressures in spite of normal sinus rhythm, due to impaction of the ball into the prosthetic ring, opening only with severe elevation of the left atrial pressure. At operation, the balls showed yellowish discoloration, but no disruption of sutures nor thrombosis of the prosthesis was found. The incidence of this phenomenon was 9% with the Cutter-Smeloff mitral prosthesis, but no such case was seen among patients with the Starr-Edwards mitral prosthesis.