The Influence of Gender on Long-Term Cardiovascular Outcomes in Patients Undergoing Percutaneous Coronary Intervention for Acute Myocardial Infarction and the Association with Cardiac Left Ventricular Function

TL;DR

Men had worse long-term cardiovascular outcomes after heart attack treatment, but this difference was reduced when considering heart structure differences.

Contribution

This study identifies left ventricular end-systolic volume index as a key factor explaining gender differences in cardiovascular outcomes after PCI.

Findings

Men had higher rates of heart failure and worse heart function metrics compared to women.

Women had better cardiovascular outcome-free survival over six years.

Adjusting for LVESVI reduced the gender difference in outcomes.

Abstract

Background/Objectives: Traditionally, women have been observed to have older age, more co-morbidities, and poorer long-term clinical outcomes following acute myocardial infarction (AMI) when compared to men. However, age-adjusted analyses have demonstrated that gender differences are often attenuated, and the potential influence of left ventricular function and structure have been infrequently studied. The aim of the present study was to evaluate how LV function could influence gender differences in the long-term incidence of a composite of clinically relevant cardiovascular outcomes. Methods: Patients treated with early PCI for AMI were examined with echocardiography 2–4 days after the index AMI and followed by a mean 73 (±13) months. The primary endpoint was the incidence of a composite of total death, recurrent myocardial infarction, hospitalization for angina pectoris with an angiogram documenting progression of coronary artery stenoses, new heart failure, evidence of stroke/transient ischemic attack (TIA), and ventricular arrhythmia. Results: Among the 236 patients studied, 179 (76%) were men, with an average age of 66 (±11) years, and 57 were women (24%), with an age of 65 (±10) years. Men exhibited a higher incidence of anterior STEMI (p = 0.030), lower left ventricular ejection fraction (LVEF) (p = 0.02), reduced global longitudinal strain (p = 0.001), and larger left ventricular end-systolic volume index (LVESVI) (p = 0.007) compared to women. Both genders had similar peak troponin T values and symptom-to-needle times, as well as an equivalent number of stents implanted, prevalence of co-morbidities, and discharge medication. After sixyears of follow-up, Kaplan–Meier curves revealed better long-term cardiovascular outcome-free survival among women (log-rank p = 0.041). Cox regression analysis indicated that neither age nor LVEF influenced this gender difference, which, however, was reduced and became non-significant when LVESVI was added (HR 1.747 (95% CI 0.89–3.43)). No difference in mortality was observed, but men had significantly higher rates of heart failure (p = 0.03). Conclusions: This study demonstrated that men with a previous PCI-treated AMI had a two-fold (HR 2.155) higher risk of a composite long-term cardiovascular outcome as compared with women. The detrimental effect of male gender remained significant after adjustments for age and LVEF, but the male gender effect was reduced and became insignificant after adjustment for age and LVESVI. In view of this, our findings indicate that higher LVESVI may partly explain the detrimental effect of male gender on cardiovascular outcomes after PCI-treated AMI.

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