The Role of Risk Factors and Trigger Factors in Cerebrovascular Events After Mitral Valve Replacement: Implications for Antithrombotic Management

Abstract

To determine the effect of risk factors and trigger factors on cerebrovascular events, 622 patients who survived mitral valve replacement between December 1979 and December 1992 were analyzed. Ninety-six patients suffered 139 nonhemorrhagic cerebrovascular events. Data were available on 138 events in 95 patients. There were 32 transient ischemic attacks (TIAs), 57 reversible ischemic neurological deficits (RINDs), and 49 strokes. Age, sex, atrial fibrillation, left atrial size, systemic hypertension, and abnormal body mass index did not discriminate between patients who suffered events and those who did not. In contrast, smoking status differed significantly between patients who suffered events and those who did not. Among current or recent ex-smokers, the risk of stroke or RIND was significantly higher than in non-smokers (p < < 0.001). The odds ratio of suffering any type of event in patients who smoked at any time postoperatively versus those who did not smoke was 2.9 (95% confidence interval: 1.8 to 4.6). Of 61 patients contacted directly, 30% recalled an infective episode immediately prior to their event. A diurnal and seasonal influence on events was also detected with peaks in the morning and in the winter months, respectively (both p < 0.001). It is concluded that there is persuasive evidence for the involvement of several nonprosthetic factors in the incidence of cerebrovascular events after mitral valve replacement. This has implications for patient management and for future analysis of prosthetic heart valve series.

Anticoagulation for mechanical heart valves: a role for patient based therapy

“…It is the consensus of most surgeons, however, that mechanical tricuspid valve prostheses are more prone to thrombosis than those in other positions [35][36][37][38]. Operative and intermediate mortality remain high following TVR [35][36][37].…”

“…The higher levels of target INR are also associated with an increased incidence of anticoagulant related hemorrhage [37]. There is no difference in survival data between mechanical or biologic prostheses [35,38].…”

Increased Carbon Monoxide Production by Hemeoxygenase‐1 Caused by Device‐Mediated Hemolysis: Thrombotic Phantom Menace?

“…As a final observation, while endogenous CO produced by HO‐1 is important to our proposed paradigm, the effects of the addition of exogenous CO to the thrombin‐enriched and hyperfibrinogenemic circulations of patients with PHVs, LVADs, and TAHs strongly support our contentions. Specifically, an impressive three‐ to fourfold increase in adverse cerebrovascular events is observed in patients that smoke tobacco and are implanted with mitral or aortic prosthetic heart valves, respectively . Even more impressive, a withering 34‐fold risk of death was observed in patients implanted with TAH that smoked in the interval between implantation and heart transplantation .…”

Comparison of mechanical and biological prostheses when used to replace heart valves in children and adolescents with rheumatic fever

“…In conclusion, our patients receiving mechanical valves suffered lower mortality and had longer periods without reoperations. When taking significant morbidity into account, however, such as haemorrhages and stroke, the incidence of adverse events became similar, justifying our choice of biological prosthesis in those patients considered at risk for problems with anticoagulation or other difficulties, this approach also being well recognized by other authors 28 – 32 …”

“…When taking significant morbidity into account, however, such as haemorrhages and stroke, the incidence of adverse events became similar, justifying our choice of biological prosthesis in those patients considered at risk for problems with anticoagulation or other difficulties, this approach also being well recognized by other authors. [28][29][30][31][32] Acknowledgement Special thanks to Prof. Evandro Coutinho of the Escola Nacional de Saú de Pú blica-Fundação Figure 5. Event-free survival of the total population studied.…”