Electrocardiographic findings in patients with polycythemia vera.

BACKGROUND: The 12-lead surface electrocardiogram (ECG) is a useful tool to predict both atrial and ventricular arrhythmias via P-wave and QT measurements and its derivatives. Polycythemia vera (PV) is a chronic myeloproliferative disorder associated with cardiovascular events. The aim of this study was to assess ECG findings of patients with PV. METHOD AND MATERIALS: Sixty patients with PV (34 male, mean age 58±11 years) and 60 age and gender-matched healthy volunteers were enrolled into the study. From the 12-lead surface ECG, P-wave and both conventional QT measurements and transmyocardial repolarization parameters (T(peak)-T(end) interval (T(p)-T(e)) and derivatives) were evaluated digitally by two experienced cardiologists. In addition, a novel parameter, Pi was calculated digitally as the standard deviation of the P-wave duration across the 12 ECG leads. RESULTS: QT duration and corrected QT interval were significantly longer in the PV group compared to healthy controls (p<0.01 and p<0.01, respectively). The T(p)-T(e) was longer and the T(p)-T(e)/QT ratio was significantly higher in the PV group compared to the controls. P-wave analyses showed that all P-wave parameters including Pmax, Pmin, P dispersion, and Pi were significantly prolonged in PV patients compared to the controls. The increase of both T(p)-T(e )and P max in the PV group was independent of age, BMI, diabetes and hypertension, gender, systolic blood pressure, hemoglobin, hematocrit, left atrial dimension, left ventricular end-diastolic diameter and early deceleration time in a univariate analysis of co-variance model (F=11.097, p=0.001 and F=31.537, p=0.0001, respectively). CONCLUSION: The present study demonstrated that PV may be associated with electrocardiographic abnormalities of both atrium and ventricle.

Assessment of left ventricular myocardial performance by tissue Doppler echocardiography in patients with polycythemia vera.

AIMS: The aim of this study was to evaluate myocardial performance index (MPI) which reflects the combined systolic and diastolic performance of the ventricles by tissue Doppler imaging (TDI) in patients with polycythemia vera (PV). METHOD AND MATERIALS: Twenty-eight patients with PV (17 men; mean age 60±9 years) and 30 age-matched healthy subjects were prospectively evaluated. The diagnosis of PV was performed according to the World Health Organization (WHO) criteria. Left ventricular (LV) systolic and diastolic functions were assessed by conventional echocardiography and TDI. MPI of both the LV and right ventricles (RV) were measured by TDI method. RESULTS: The LV MPI was significantly higher in PV group than in the controls (0.61±0.16 vs. 0.49±0.05; P=0.001). Also, the RV MPI was impaired in patients with PV compared to the control subjects (0.51±0.11 vs. 0.43±0.09; P=0.005). RV late A filling velocity (Am) and RV isovolumetric relaxation time were significantly higher in the PV group compared to healthy subjects (P=0.03 and 0.05, respectively). In logistic regression models, PV was determined as an independent predictor of impaired MPI (odds ratio: 3.7; CI 95%, 1.2-7.5). In addition, pulmonary arterial pressure was significantly elevated in patients with PV compared to the controls (P=0.02). CONCLUSION: This study demonstrated that biventricular MPI is impaired in patients with PV.