Cardiovascular outcome trials –⁠ How to interpret their results, what to focus on, and their relevance for clinical practice

Czech version

Authors: Tomáš Bolek
Authors‘ workplace: Pracovisko invazívnej a intervenčnej kardiológie SÚSCH a. s. Banská Bystrica ; I. interná klinika Jesseniova lekárska fakulta v Martine, Univerzita Komenského v Bratislave ; Pracovisko intervenčnej kardiológie, Fakultná nemocnica s poliklinikou Žilina
Published in: Forum Diab 2026; 15(1): 76-80
Category: Review Article

Overview

Cardiovascular outcome trials (CVOTs) have become a cornerstone in the evaluation of safety and efficacy of modern cardiometabolic therapies. However, their interpretation goes beyond a simple assessment of the primary endpoint and requires a comprehensive understanding of study design, patient population, and the nature of selected clinical outcomes. The aim of this review is to outline key principles for interpreting CVOTs, highlight common pitfalls, and discuss their relevance for everyday clinical practice. Using the SURPASS-CVOT and SUMMIT trials as examples, we demonstrate that the clinical benefit of therapy is strongly dependent on disease phenotype and mechanism of action. While SURPASS-CVOT confirmed the non-inferiority of tirzepatide in reducing major adverse cardiovascular events, the SUMMIT trial showed significant improvements in symptoms, functional capacity, and reduction in heart failure worsening in patients with obesity-related HFpEF. CVOTs therefore represent not only a regulatory requirement but also a critical source of evidence for treatment individualization. Their proper interpretation enables more precise targeting of therapy according to specific clinical phenotypes and improves patient management in routine practice.

Keywords:

obesity – cardiometabolic risk – tirzepatide – cardiovascular outcome trial (CVOT) – heart failure with preserved ejection fraction (HfpEF)

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