Sixty hypertensive individuals with confirmed left ventricular hypertrophy (LVH) on echocardiography constituted the study cohort. If a patient's blood pressure was measured at more than 140/90 mm Hg on one or more outpatient visits, had a history of hypertension, or was started on antihypertensive medication, they were diagnosed with hypertension. The patients' recommended anti-hypertensive medications remained unchanged. No sedatives, antipsychotics, or antiarrhythmics (apart from beta-adrenergic blockers) were administered to the patient. Informed consent was given by the patients. For men, a left ventricular mass index (LVMI) of greater than 115 g/m2 and for women, greater than 95 g/m2 was considered left ventricular hypertrophy.

In cases where technically appropriate echocardiographic images could not be acquired, patients were excluded from the study protocol. Individuals having a history of atrial fibrillation or CAD were not accepted. To rule out any concomitant arrhythmogenic conditions, patients were excluded if their echocardiogram revealed asymmetric septal hypertrophy (septal to posterior free wall thickness ratio > 1.3), left ventricular dilation (diastolic left ventricular diameter > 5.8 cm), impaired ventricular systolic function (ejection fraction (EF) less than 50%), or significant valve disease.

A qualified cardiologist evaluated each patient's echocardiogram using the standard views—parasternal, short-axis, and apical—while positioning them in the left lateral position, in compliance with the American Society of echocardiogram guidelines [12]. Three heartbeats were averaged for the assessment. The following measurements were made of the left ventricle's internal diameter in systole (LVIDS) and diastole (LVIDD), as well as the interventricular septal thickness at end diastole (IVSTd) and posterior wall thickness at end diastole (PWTd).

LVM was computed utilizing the modified Devereux formula [13]:

$$} = 0.\left[ .0\;\left( } + } + }} \right)^} - \left( }} \right)^} } \right] + 0.\;}.$$

Left ventricular mass index (LVMI) was calculated after dividing LVM by body surface area (LVM/BSA, g/m2).

The formula used to compute the body surface area (in square meters) was 0.0001 × 7l.84 (weight in kg)0.425 × (height in cm) 0.725 [14].

Cardio UP three-channel recorders were used to capture all ambulatory ECG tracings throughout 48 monitoring hours. Each tape was scanned and reviewed for detailed analysis by two cardiologists who did not know the results of other investigations.

The frequency of premature ventricular beats (VPB) as a percentage of the total heart rate per 24 h in Holter monitoring and the complexity of ventricular premature beats according to Lown and Wolf [15].

0 No VPB

1 Occasional, isolated VPB

2 Frequently occurring VPBs; more than 1 per minute or more than 30 betas per hour

3 Multiform VPB

4(a) Repetitive VPB: couplets

4(b) Repetitive VPB: salvos

5 Early VPB

We further classified them into low grades (Lown grades 1,2 and 3) and high grades (Lown grades 4a, 4b, and 5).

The Statistical Package for Social Sciences (SPSS ver.28 Chicago, IL, USA) was used to analyze the data. Data were presented using mean and standard deviation (SD), and the K-S test was used to test for normality. Frequency and percentage descriptions were provided for the qualitative variables. The high and low Lown grade groups were compared using an independent sample t-test. The diagnostic accuracy of LVMI was tested using ROC curve analysis, and the cutoff point with the best sensitivity and specificity was identified. The prediction of increasing VPC complexity (Grades 4a, 4b, 5 vs. grades 1, 2, 3) was made using multivariate logistic regression analysis. Predictors were included in the regression models using the enter technique, and significant contributing variables were identified by calculating the adjusted odds ratio with a 95% confidence interval. The percentage of VPCs in total HR was predicted using multiple linear regression analysis, along with the computation of beta coefficients and t-tests. There was no multicollinearity among the predictors when the assumption of multicollinearity was verified using VIF tolerance. A p-value of 0.05 was considered statistically significant.