In-hospital Mortality and Outcome Predictors in a Large Seven Year Cohort of Patients Admitted for Ventricular Tachycardia

Background:

Patients hospitalized for ventricular tachycardia (VT) are at risk for severe deterioration, potentially resulting in cardiogenic shock and increased in-hospital mortality. Catheter ablation (CA) of VT is indicated when drugs are ineffective and might prevent a negative course.

Aim:

The aim of this study was to identify predictors for in-hospital mortality and to compare in-hospital outcomes in patients undergoing CA of VT with patients not undergoing CA of VT.

Methods:

Consecutive patients hospitalized due to VT between 2017 and 2024 at our center were retrospectively analyzed. Occurrence of VT in the setting of an acute ST-segment elevation myocardial infarction were excluded. Patient demographics, CA of VT, and in-hospital outcomes were identified using ICD-10- and OPS-codes. Patients were classified as either receiving CA of VT or not receiving CA of VT within the same hospital stay and compared for the primary outcome of in-hospital mortality. Secondary outcomes consisted of cardiogenic shock requiring extracorporeal membrane oxygenation (ECMO), ICU admission, need of mechanical ventilation, peak blood lactate concentration, and peak N-terminal prohormone of brain natriuretic peptide (NT-pro-BNP) concentration. Models were calculated to assess the effect of age, sex, CA of VT, and ischemic/non-ischemic cardiomyopathy on in-hospital mortality.

Results:

In total, 6168 patients were hospitalized due to VT without ST-segment elevation myocardial infarction (mean age 67±15 years, 34% female, 15% ischemic cardiomyopathy, 11% non-ischemic cardiomyopathy, 24% New York Heart Association class III or IV heart failure, 10% after successful cardiopulmonary resuscitation). Mean left ventricular ejection fraction (LVEF) was 45±15%. Acute cardiac decompensation requiring i.v. furosemide was present in 916 (17%) patients. CA of VT was performed in 1050 (18%) patients. The overall in-hospital mortality rate was 11% (656 patients). When adjusted for age, sex, and ischemic/non-ischemic cardiomyopathy, CA of VT was associated with a reduced risk for in-hospital mortality (OR 0.03, 95% CI 0.01-0.07, p<0.001). When adjusted for CA of VT, female patients were at lower risk (OR 0.69, 95% CI 0.57-0.83, p<0.001), and patients with ischemic-cardiomyopathy at higher risk (OR 1.52, 95% CI 1.22-1.89, p<0.001) for in-hospital mortality (Figure 1). Cardiogenic shock requiring ECMO occurred less often after CA of VT (0.7% vs. 5.0%, p<0.001), and time to discharge was shorter (median 3 days [IQR 2-7] vs. 7 days [IQR 3-16], p<0.001). Patients who did not undergo CA of VT were more frequently admitted to the ICU (28% vs. 5.1%, p<0.001), and more often needed mechanical ventilation (22% vs. 1.6%, p<0.001). Peak concentrations for blood lactate were similar (median 2.2 [IQR 1.4-4.9] vs. 1.7 [IQR 1.1-2.4], p=0.42), however, peak concentrations for NT-pro-BNP were two-fold higher in patients who did not undergo CA of VT (median 2,849 [IQR 740-8,249] vs. 1,328 [IQR 436-4,140], p<0.001).

Conclusion:

This large in-hospital data set on patients admitted for VT revealed that CA of VT and female sex significantly reduced in-hospital mortality. Furthermore, the rate of cardiogenic shock requiring ECMO, admission to the ICU, and the need for mechanical ventilation were significantly lower in patients undergoing acute CA of VT compared to patients who did not undergo CA.