Age thresholds for prophylactic replacement of Björk-Shiley convexo-concave heart valves. A clinical and economic evaluation.

BACKGROUND: Björk-Shiley convexo-concave heart valves have an increased risk of mechanical failure. One might consider prophylactic rereplacement as a preventive measure to avert the disastrous consequences of these failures. We investigated the effect that prophylactic rereplacement has on survival of individual patients and on the medical costs. METHODS AND RESULTS: Quantitative estimates for the surgical risks of prophylactic replacement of Björk-Shiley valves, long-term survival, and the risk of outlet strut fracture were derived insofar as possible from a detailed analysis of a follow-up study conducted in The Netherlands, including 2303 patients with a mean follow-up of 6.6 years. On the basis of these estimates, we calculated life expectancy with and without prophylactic replacement. For the various valve types, age thresholds were determined below which rereplacement prolongs (discounted quality-adjusted) life expectancy. We also calculated the cost per year of life gained as a function of age. The age thresholds below which prophylactic rereplacement increases life expectancy (expressed in simple future years of life) for male patients without comorbidity, if the surgical mortality after rereplacement is equivalent to that of primary replacement, are 27, 48, 51, and 65 years for small and large 60 degrees and for small and large 70 degrees mitral valves, respectively. For aortic valves, these age thresholds lie somewhat higher: 39, 52, 56, and 76 years, respectively. Repeat analyses indicated that for women, all age thresholds lie about 1 or 2 years higher. These age thresholds decrease considerably if the surgical mortality after rereplacement is considered to be higher after prophylactic rereplacement than after primary replacement or if comorbidity is present. The costs per discounted and quality-adjusted year of life gained depend on type and position of the Björk-Shiley convexo-concave heart valve and rise steeply as the patient's age approaches the threshold for rereplacement. CONCLUSIONS: The results of the Dutch follow-up study allow guidance for prophylactic replacement of the Björk-Shiley convexo-concave valve on an individual basis. Rereplacement compares favorably with expectant management in some patient subgroups with both 60 degrees and 70 degrees valves. Age thresholds may serve as a first step in identifying patients in whom rereplacement might be beneficial.

Early surgery for active infective endocarditis improves early and late results.

To investigate the timing of surgery in active infective endocarditis, the data of 54 patients, consecutively operated for this reason from September 1973 to May 1989, were analysed. Native valves were involved in 31 patients (57%): the aortic valve in 22, the mitral valve in 6, and both valves in 3 cases. Prosthetic valves were involved in 23 patients (43%): the aortic valve in 14, the mitral valve in 7, and both valves in 2 cases. There were no significant differences between involvement of native or prosthetic valves and mortality, morbidity, or consequences of morbidity. No significant correlation was found between causative microorganism and mortality, morbidity, or consequences of morbidity. The indication for operation was cardiac failure in 15 patients (28%), ongoing infection in 24 (44%) or a combination of these in 15 (28%). Major embolization occurred in 12 patients (22%) and affected women more than men (p = 0.05). Hospital mortality was 8 (15%). Morbidity involved 15 more patients; structural deterioration of the valve prosthesis occurred in 1 patient; nonstructural dysfunction of the valve prosthesis occurred 11 times in 10 patients; anticoagulation-related hemorrhage involved 2 patients (1 with nonstructural dysfunction of the valve prosthesis); endocarditis was diagnosed in 3 patients. The consequences of these morbid events concerned 14 patients; reoperations were done 9 times in 8 patients; mortality was valve related in 6 cases. Because 2 more patients died during the course of the study, total late mortality was 8. Probability of survival 5 years after operation was 72% (95% cl 56-83) and at 10 years 47% (95% cl 21-70).(ABSTRACT TRUNCATED AT 250 WORDS)

Ventricular free wall rupture: sudden, subacute, slow, sealed and stabilized varieties.

Six cases of acute myocardial infarction with blood in the pericardial sac are described. In one case rapid death followed myocardial rupture leaving no time for the possibility of intervention. Of two other cases acute symptoms developing after myocardial rupture, one was operated on promptly and the other, whose condition improved on pericardiocentesis, after a delay of a few hours. Both are now long term survivors A fourth patient probably had two episodes of rupture which apparently sealed off. He underwent cardiac catheterization, but no epicardial leak was found. Subsequently at operation a sealed myocardial rupture was detected and sutured over. The fifth patient suffered a silent myocardial rupture. A false aneurysm was diagnosed four months later and he withstood successful surgery. In the sixth patient, the course was similar to that of case 1, namely rapid death with a clinical picture suggestive of tamponade. Postmortem examination showed a covert rupture with some evidence of attempts to plug the opening. The purpose of this report is to emphasize the varying course which myocardial rupture can take.

Echocardiography and rupture of the heart.

In four patients with rupture of the free wall of the left ventricle, the diagnosis was made at the bedside using a portable cross-sectional echocardiograph; this was confirmed at necropsy in two patients and by paracentesis in the other two. Weak ventricular contractions were seen after each QRS complex of the electrocardiogram, contradicting a widespread belief that cardiac rupture immediately produces electromechanical dissociation. In one patient aspiration of 100 ml blood from the pericardium allowed resumption of cardiac pump function; this patient survived for three days but was allowed to die because of cerebral damage sustained during resuscitation.