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Sudden heart arrest (HA) in the early phase after aorto coronary bypass surgery represents a serious event necessitating resuscitation, and for those who survive usually also an extra stay in the coronary care unit. Since such episodes of heart standstill may be related to conduction defects, a study was conducted to determine whether the duration of the QRS complex on the preoperative ECG is a marker for this morbid event. A cohort of 1011 consecutive patients operated on between 1982 and 1986 and followed to January 1st, 1993 were included in the study. Incidence of lethal or non-lethal HA during the first 4 weeks after surgery was considered as the primary endpoint and total mortality as the secondary endpoint. The incidence of HA was 40/1011 = 4%, with the majority of events (60%) being lethal. Independent risk factors of HA using the multivariate logistic model were previous coronary artery bypass surgery, presence of mitral regurgitation, left ventricular ejection fraction and the intraoperative cross-clamp time of aorta. Adjusting for the effect of confounder variables showed that the gradient effect of QRS complex duration on the endpoint HA was still present (p = 0.012). The duration of the QRS complex taken from the preoperative ECG had a gradient effect on the incidence of HA. With a baseline level of QRS <70 ms, the following odds ratios (OR) for HA were found: OR = 1.38 (95% CI 0.60-3.31) for QRS 70-80 ms; OR = 2.27 (95% CI 0.87-5.90) for QRS >90-120 ms; and OR = 3.38 (95% CI 1.06-11.50) for QRS >120 ms, when adjusting for the risk factors. Cumulative survival at 5 years after surgery was 28 ± 7.1% for patients experiencing HA versus 87 ± 1.2% for patients free from this event. Our results underline the importance of the QRS complex duration as a preoperative marker for HA after aorta coronary bypass surgery, when adjusting for other risk factors. Although the one-year survival is poor for patients experiencing HA, there is no increase in mortality during the late follow-up. [ABSTRACT FROM AUTHOR]

The present study reports on the incidence and degree of intravascular haemolysis in 33 patients with Björk-Shiley tilting disc prosthesis and in 34 patients with Lillehei-Kaster pivoting disc valve prosthesis in the mitral position examined 12 to 24 months after the operation. Serum haptoglobin, serum lactate dehydrogenase, serum bilirubin, and haemoglobin estimations were performed. Significant haemolysis was detected in 85 per cent of the patients. Haptoglobin was absent or reduced in 72 per cent, while raised values for serum lactate dehydrogenase were found in 43 per cent. The increase in lactate dehydrogenase was moderate and showed no correlation with blood flow through the prosthesis or with the gradient across the prosthesis. Most patients had normal haemoglobin and normal serum bilirubin values. Although intravascular haemolysis was of little clinical significance, the increase in lactate dehyrdrogenase was significantly higher in patients with the Lillehei-Kaster prosthesis than in patients with the Björk Shiley prosthesis, indicating a slightly shorter red cell lifespan in the former group. The possible reasons for the difference between the two groups are discussed. [ABSTRACT FROM PUBLISHER]

Cardiac stroke volume was measured simultaneously by Doppler echocardiography and thermodilution in patients with severe coronary artery disease. One group (20 patients) was examined during supine exercise at 25 W and a second group (20 patients) during sitting exercise at 25 W and 50 W. In a third group (10 patients) the reproducibility of the non-invasive stroke volume estimate was determined during upright exercise. There was a considerable variation between results obtained with the invasive and non-invasive technique at rest and during exercise, but no systematic differences were found. Analysis of variance showed that no systematic differences between ultrasonic results were introduced by two observers or by measurements on different days. The coefficient of variation between any pairs of Doppler measurements in each patient was 6%. These findings demonstrate that the ultrasonic technique is suitable for detecting changes in stroke volume induced by low load exercise in patients with severe angina pectoris. [ABSTRACT FROM PUBLISHER]

In an attempt to develop a new approach to the non-invasive measurement of aortic regurgitation, transmitral volumetric flow (MF) and left ventricular total stroke volume (SV) were measured by Doppler and cross sectional echocardiography in 23 patients without aortic valve disease (group A) and in 26 patients with aortic regurgitation (group B). The transmitral volumetric flow was obtained by multiplying the corrected mitral orifice area by the diastolic velocity integral, and the left ventricular total stroke volume was derived by subtracting the left ventricular end systolic volume from the end diastolic volume. The aortic regurgitant fraction (RF) was calculated as: RF = 1 - MF/SV. In group A there was a close agreement between the transmitral volumetric flow and the left ventricular total stroke volume, and the difference between the two measurements did not differ significantly from zero. In group B the left ventricular total stroke volume was significantly larger than the transmitral volumetric flow, and there was good agreement between the regurgitant fractions determined by Doppler echocardiography and radionuclide ventriculography. Discrepancies between the two techniques were found in patients with combined aortic and mitral regurgitation or a low angiographic left ventricular ejection fraction (less than 35%). The effective cardiac output measured by Doppler echocardiography accorded well with that measured by the Fick method. Doppler echocardiography provides a new and promising approach to the non-invasive measurement of aortic regurgitation. [ABSTRACT FROM PUBLISHER]

In an attempt to develop a new approach to the non-invasive measurement of mitral regurgitation, Doppler echocardiography and left ventriculography were performed in 20 patients without valvar heart disease (group A) and in 30 patients with pure mitral regurgitation (group B). Volumetric flows through the aortic and the mitral orifices were determined by Doppler echocardiography. Aortic flow (AF) was calculated as the product of the aortic orifice area and the systolic velocity integral. The mitral flow (MF) was calculated as the product of the corrected mitral orifice area and the diastolic velocity integral. The mitral regurgitant fraction (RF) was calculated as RF = 1 - AF/MF. In group A aortic and mitral flow were very similar and the difference between the two did not differ significantly from zero. In group B the mitral flow was significantly larger than the aortic flow. There was a good correlation (r = 0.82) between the regurgitant fraction determined by Doppler echocardiography and the regurgitant grades determined by left ventriculography. The regurgitant fraction increased significantly with each grade of severity. These results show that Doppler echocardiography can be used to give a reliable measure of both aortic and mitral flow. This technique is a new and promising approach to the non-invasive measurement of mitral regurgitation. [ABSTRACT FROM PUBLISHER]

Cardiac output was determined in 20 patients with various cardiac conditions by measuring the cross sectional area of the mitral orifice by echocardiography and the transmitral flow by the Doppler technique. Cardiac output was calculated by multiplying the corrected mitral orifice area by the maximum diastolic velocity integral recorded by the pulsed mode. The results were compared with that obtained by the Fick method. The correlation for cardiac output by the two techniques was high in the whole group, particularly in patients without mitral regurgitation. There was also a good correlation for stroke volume determined by the two methods. Cardiac output was significantly overestimated by the continuous mode and in patients with mitral regurgitation. These results show that the mitral orifice method provides a new and reliable approach to the non-invasive measurement of cardiac output. [ABSTRACT FROM PUBLISHER]

A combination of M mode and Doppler echocardiography was used to study patients with mitral disc valve prostheses. The probe used in these investigations consisted of a circular Doppler crystal mounted around the M mode crystal in the same plane. Because of the strong echoes produced by the prosthesis the transducer (probe) could be angled for optimum Doppler signals without losing the M mode echocardiographic recording of the prosthesis. With this equipment mean and maximum blood velocities and Doppler amplitude signals could be measured simultaneously with M mode echocardiography. A depth indication line in the M mode recording ensured that the Doppler signal was recorded in the region of interest. The Doppler ultrasound technique was also used separately in both the pulsed wave and the continuous wave mode. The data show the usefulness of this technique in patients with normally functioning valve prostheses and in three patients with valve malfunction due to thrombus formation. The data in the latter three cases seem to indicate that the Doppler technique provides valuable information in addition to that obtained by M mode echocardiography in recognising mitral valve prosthetic malfunction. [ABSTRACT FROM PUBLISHER]

Cardiac output determined by Doppler echocardiography was compared with that determined by thermodilution at rest and during dobutamine infusion in 10 patients (group A) and by the Fick method at rest in 11 patients (group B). All patients had angina pectoris without valvular heart disease. Maximum spatial blood velocity and cross sectional aortic area were estimated by the Doppler technique and echocardiography. Cardiac output was calculated by multiplying blood velocity by aortic area at various levels in the ascending aorta. The best correlation of cardiac output between the invasive and non-invasive methods was obtained when maximum velocity in the aortic root and the aortic orifice area were used in the calculations. Cardiac output was considerably overestimated when area measurements in the aortic root were used. [ABSTRACT FROM PUBLISHER]

Clinical and haemodynamic findings were reviewed in 109 consecutive patients in whom an isolated ventricular septal defect was diagnosed after the age of 15 years (range 15-65 years). Most patients had no or minor cardiac symptoms. Based on the left to right shunt size and pulmonary pressure, 32 (29%) patients had large and 75 (69%) small ventricular septal defects, whereas in two (2%) patients data were insufficiently complete for determining the size. The anatomical location was membranous in 92% and muscular in 8% of the 51 patients in whom this could be assessed from a left ventricular angiogram or the surgeon's report of a subsequent operation, or both. Nine (8%) patients had developed the Eisenmenger syndrome, 12 had aortic regurgitation, and 16 (15%) had bacterial endocarditis, the incidence of the latter being 5.7 per 1000 patient years. Of the 34 (31%) patients who underwent surgery, five (15%) died while in hospital. In contrast with reports from paediatric series our study in adults showed a predominance of small ventricular septal defects and a high frequency of irreversible pulmonary hypertension and serious complications, such as aortic regurgitation and bacterial endocarditis. Thus ventricular septal defects in adults should--regardless of symptoms--be looked on as potentially serious. [ABSTRACT FROM PUBLISHER]

Myocardial scintigraphy with thallium-201 and electrocardiogram-gated left ventriculography with technetium-99m labelled red blood cells were applied in four groups of subjects: 25 with no signs or symptoms of cardiovascular disease (group 1), 28 with a "false" positive exercise electrocardiogram (group 2), 14 with angina pectoris and normal coronary angiograms (group 3), and 43 with angina pectoris and fixed coronary artery stenoses (group 4). In groups 1 and 4 the radionuclide findings were in accordance with clinical and invasive measurements. In groups 2 and 3 the most important finding was the lack of increase in left ventricular ejection fraction during exercise in about half of these subjects (even a decrease in 25%), indicating subnormal myocardial reserve. The additional finding of pathological myocardial biopsies in four of these patients suggests that asymptomatic ST depression in patients with normal coronary angiograms may in some cases represent an early, preclinical sign of cardiomyopathy. [ABSTRACT FROM PUBLISHER]

The haemodynamic effects of nifedipine, propranolol, and the combined administration of the two drugs were studied in 12 patients with hypertrophic obstructive cardiomyopathy. The combined administration of nifedipine and propranolol appeared to be superior to that of nifedipine alone. The spontaneous heart rate was reduced in most cases after nifedipine plus propranolol, and at atrial pacing the following results were obtained: left ventricular peak systolic pressure was reduced from 200 +/- 39 to 157 +/- 30 mmHg; a positive correlation was found between the pre-drug left ventricular end-diastolic pressure and the magnitude of reduction in left ventricular end-diastolic pressure; systolic blood pressure was reduced from 125 +/- 31 to 111 +/- 27 mmHg, and total peripheral resistance was reduced from 1403 +/- 307 to 1160 +/- 209 dyne s-1 cm-5. The combined administration reduced the resting left ventricular outflow gradient from 76 +/- 19 to 45 +/- 26 mmHg, while cardiac index was left unchanged. The effects on mean pulmonary arteriolar resistance and mean pulmonary arteriolar resistance and mean pulmonary capillary venous pressure were in most cases slight and insignificant. The results indicate an improved haemodynamic condition in patients with hypertrophic obstructive cardiomyopathy after the combined administration of nifedipine and propranolol: a treatment that might provide a new and useful alternative to already existing medication. [ABSTRACT FROM PUBLISHER]

Sixty-six consecutive patients less than 40 years of age with angiographically documented coronary artery disease and coronary heart disease took part in a study aimed at (1) identifying the presence of factors which might explain the premature onset of ischaemic heart disease, and (2) assessing the distribution and severity of the coronary artery lesions. For comparisons we have used a study of risk factors in 1832 men defined as "normals" according to a recent comprehensive examination. The findings show that the typical early onset coronary heart disease case is an overweight, heavily smoking male "blue collar" worker, with high serum levels, a marginally raised blood pressure, and a high prevalence of coronary heart disease among first degree relatives. Coronary angiography showed a preponderance of one vessel disease. In particular, left anterior descending artery lesions were common, which might have contributed to the early manifestation of disease. [ABSTRACT FROM PUBLISHER]

Twenty-six patients (21 men and five women) with a mean age of 54.8 years have been reinvestigated nine to 62 months (mean 29.7) after left ventricular aneurysmectomy. Preoperatively left ventricular angiography disclosed an anterior aneurysm in all cases, which was large in 15 (57%) and small to medium in 11 (42%). At follow-up a large residual aneurysm was found in five (19%), a small to medium one in 13 (50%), and akinesia without aneurysm in eight (31%). The sum of ST elevation (sigma ST) in praecordial leads in the electrocardiogram was reduced from a mean value of 11.2 mm to 7.7 mm. In no patient did ST segments return to normal after operation. Preoperatively, mean sigma ST was identical in patients with large and with small to medium aneurysms. At reinvestigation mean sigma ST was identical in patients with large and with small to medium residual aneurysms as well as in patients with akinesia. Left ventricular end-diastolic pressure before angiography was reduced from a mean value of 21.5 mm to 15.1 mmHg and after angiography from 26.7 mm to 21.1 mmHg. Progression of coronary artery stenoses was a characteristic finding in patients whose left ventricular end-diastolic pressures did not return to normal. These patients had a longer follow-up time than those with no progression of coronary disease, who all showed an improvement in left ventricular end-diastolic pressure. Six patients who had coronary bypass grafting performed had unchanged left ventricular end-diastolic pressures at follow-up. The results indicate that progression of coronary artery disease may be responsible for an eventual further deterioration in left ventricular function after aneurysmectomy. Additional bypass grafting did not result in improved left ventricular function. [ABSTRACT FROM PUBLISHER]

The occupational status of a group of 100 male patients, 35 to 68 years of age, with chronic ischaemic heart disease was studied, and related to the severity and distribution of coronary artery stenosis seen on the arteriograms and to left ventricular function. In this series of patients 31 per cent were working, 31 per cent were recorded as temporarily sick, and 38 per cent as permanently disabled. It appears that while the type of previous occupation and physical activity associated with the job were of importance, there was no correlation between employability on the one hand and severity and distribution of coronary artery disease on the other. 'Blue-collar' workers had a higher rate of unemployment than those in 'white collar' occupations, but this could not be explained by differences in severity of coronary artery disease. [ABSTRACT FROM PUBLISHER]

1 The time-related, comparative beta-adrenoceptor blocking effect of metoprolol 150 mg twice daily, atenolol 100 mg once daily and pindolol 7.5 mg twice daily on heart rate, blood pressure, work performance, blood lactate, free fatty acids and plasma catecholamines was studied in ten males aged 19-25 years by means of repeated maximal bicycle exercise tests. 2 At steady state several differences in effects were noted among the drugs. These could be explained by differences in beta 1-selectivity, potency of the chosen drug-doses and intrinsic sympathomimetic activity (ISA). 3 This study emphasizes the importance of including strong sympathetic stimuli in any model used for comparing beta-adrenoceptor blockers with and without ISA in order not to underrate the effects of beta-adrenoceptor blockers with ISA. 4 In the chosen doses pindolol was more effective, and atenolol less effective than metoprolol in suppressing heart rate and blood pressure responses to maximal exercise. [ABSTRACT FROM AUTHOR]