DIFFERENTIAL DIAGNOSIS OF HYPERTROPHIC CARDIOMYOPATHY AND HYPERTENSIVE HEART DISEASE BY EXERCISE TESTING

Abstract

Aim. To assess the effectiveness of a bicycle ergometer exercise test in differentiation of hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD). Material and methods. 42 patients with HCM (mean age 49,8±15,3-28 male) and 25 patients with HHD (mean age 47,0±12,4-16 male) were studied. All patients underwent upright bicycle ergometer exercise test after withdrawal of drug therapy. Results. It is well-known that abnormal blood pressure response (ABPR) and ST depression with angina during exercise are the criteria for the termination of test (RTT) and are the HCM attributes (after ruling out the coronary atherosclerosis by coronarography). With the use of nonparametric statistics we found significant difference between HCM and HHD in systolic blood pressure (SBP) at the end of the test (174,6±30,8 and 210,4±21,1 mmHg; p=0,000006), time recovery after test (TR) (10,0±4,0 and 7,1±1,6 min; p=0,007), breathlessness as a RTT (38,4% and 4%, p=0,022); extrasystole as a RTT (12,5% and 0%). With the use of logistic regression we found a dependency for differential diagnosis of HCM and HHD: Diagnosis = 0,41*SBPe-40,79-3,65*TR-13,34*BR-41,87*EXT-1000*0^TH. Where SBPe is SBP at the end of the test; TR equals 1 if breathlessness was the RTT and 0 otherwise; EXT equals 1 if extrasystole was the RTT and 0 otherwise; OTH equals 1 if ABPR, ST depression or stenocardia were the RTT and 0 otherwise. Diagnosis is greater than 0 for HHD and less than 0 for HCM patients. For all patients included in our study the dependency provides correct result. Conclusion. The exercise testing gives useful information and can be applied for differential diagnosis of HCM and HDD.