Key result
Elevated resting RV-to-LV blood flow ratio linked to ~4.5-fold higher risk of heart failure hospitalization or CV death.
Why the study?
Quantitative cardiac PET is well established for assessing LV ischaemia, but the clinical significance of RV myocardial blood flow and the sex-specific diagnostic and prognostic value of the resting RV/LV MBF ratio remained unclear.
Does a resting biventricular myocardial blood flow ratio (MBFRV/LV) measured by cardiac 15O-water PET predict major adverse cardiac events in symptomatic patients with known or suspected chronic coronary syndromes?
Cohort (n=783)
Does a resting biventricular myocardial blood flow ratio (MBFRV/LV) measured by cardiac 15O-water PET predict major adverse cardiac events in symptomatic patients with known or suspected chronic coronary syndromes?
An elevated resting RV-to-LV myocardial blood flow ratio (>67%) measured by 15O-water PET independently predicts acute heart failure hospitalization or cardiovascular death, particularly in females, serving as a novel marker of adverse ventricular loading and heart failure risk.
Elevated ratio may identify higher HF risk warranting closer surveillance; leaves open whether it adds value beyond LVEF and NT-proBNP.
Background Quantitative cardiac PET is well established for assessing left ventricular (LV) ischaemia, but the clinical significance of right ventricular (RV) myocardial blood flow (MBF) remains unclear. Purpose We investigated the diagnostic and prognostic value of the ratio between RV and LV resting MBF (MBFRV/LV) as a potential PET-based marker of abnormal RV loading, with a focus on sex-specific differences. Methods A clinical cohort of 783 symptomatic subjects with known or clinically suspected chronic coronary syndromes referred for cardiac 15O-water PET was retrospectively included. MBFRV/LV was analysed in relation to traditional risk factors, comorbidities associated with manifest cardiac disease, echocardiography, biomarkers, stress PET findings, and major adverse cardiac events (MACE: acute heart failure [HF] hospitalization or cardiovascular death). Results MBFRV/LV was narrowly regulated in low-risk subjects (mean 51±8%). It increased progressively with traditional risk factors—particularly in females—and was independently associated with hypertension, obesity, and LV ischaemia. Higher MBFRV/LV correlated with NT-proBNP and echocardiographic markers of diastolic dysfunction, including elevated E/e′ and RV systolic pressure. A value above 67% predicted MACE (HR 4.5 [95% CI 2.8–7.3]) and remained independently prognostic after adjustment for HF history, LV ejection fraction, and myocardial flow reserve (MFR). In females without known HF, MBFRV/LV predicted outcomes independently of MFR. Conclusions The RV/LV perfusion ratio derived from standard PET imaging reflects sex-specific vulnerability to adverse ventricular loading. MBFRV/LV identifies patients—especially females—with increased HF risk, independent of LV systolic or microvascular function, and may serve as a novel marker of HF pathophysiology.
No takes yet. Share an insight, caveat, or question.
Svanstrom et al. (2026) conducted a cohort in Known or clinically suspected chronic coronary syndromes (n=783). Resting RV to LV myocardial blood flow ratio (MBFRV/LV > 67%) vs. MBFRV/LV <= 67% was evaluated on Major adverse cardiac events (MACE: acute heart failure hospitalization or cardiovascular death) (HR 4.5, 95% CI 2.8-7.3). A resting RV-to-LV myocardial blood flow ratio above 67% on PET predicted acute heart failure hospitalization or cardiovascular death (HR 4.5; 95% CI 2.8-7.3).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: