Abstract Introduction According to the literature, the annual mortality rate of hypertrophic cardiomyopathy (HCM) patients is estimated to 1–2%. Sudden cardiac death (SCD), heart failure and thromboembolism are the main causes of death among this population. Patients at high risk for SCD, identified using HCM risk score, are qualified for ICD implantation. Unfortunately for clinicians, there is no validated model or statistical tool for assessment of the risk of mortality within the HCM patients with ICDs. Purpose The aim of this study was to determine the main risk factors of all- cause mortality in HCM patients with ICDs. Methods The long-term follow-up of group of 104 consecutive patients with HCM, who had the ICD implanted between 1996 and 2006 in tertiary reference clinical unit was performed. Twenty patients who died during observation were the subject of the current analysis. ICD was implanted for primary (n=16) and secondary (n=4) prevention of SCD within this subpopulation. Analysis were performed for mentioned below potential risk factors: age at the time of implantation, syncopes, family history of SCD, atrial fibrillation/supraventricular tachycardia, decreased left ventricular ejection fraction (LVEF), non-sustained ventricular tachycardia (nsVT), maximum left ventricular wall thickness, abnormal exercise blood pressure response, left ventricular outflow tract obstruction. Results The average time of survival since ICD implantation was 8,5±4,6 years. Decreased LVEF (Wald chi2 4,57; p=0,033), secondary prevention (Wald chi2 8,57; p=0,003), family history of SCD (Wald chi2 4,93; p=0,026) and episodes of nsVT (Wald chi2 3,49; p=0,062) are the clinical risk factors that significantly affect the time of survival. The probability of death, expressed as Hazard Ratio, was 27-fold higher in secondary prevention group (HR=27,18), almost 10-fold higher in patients with positive family history of SCD (HR=9,74) and 3,7-fold higher when nsVT was detected. The cause of death was established in 16/20 patients. In 15 cases, these were deaths from cardiovascular causes: end-stage heart failure (8), complications of heart transplantation or circulatory support (4), SCD (1) and other cardiovascular (2). Conclusion Secondary prevention, positive family history of SCD, nsVT and decreased LVEF seem to be the most significant risk factors associated with all- cause mortality in HCM patients with ICDs. Despite the ICD implantation, subpopulation studied had poor prognosis with high incidence of progression to end-stage heart failure. Further studies to create validated model for assessment of death risk in long-term observation of patients with HCM after ICD implantation are required.
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