ABSTRACT
BACKGROUND: Right ventricular (RV) dysfunction is known to impact prognosis, but its determinants in coronary artery disease are poorly understood. Stress cardiac magnetic resonance (CMR) has been used to assess ischemia and infarction in relation to the left ventricle (LV); the impact of myocardial tissue properties on RV function is unknown. METHODS: Vasodilator stress CMR was performed in patients with known coronary artery disease at 7 sites between May 2005 and October 2018. Myocardial infarction was identified on late gadolinium enhancement-CMR, and infarct transmurality was graded on a per-segment basis. Ischemia was assessed on stress CMR based on first-pass perfusion and localized by using segment partitions corresponding to cine and late gadolinium enhancement analyses. RV function was evaluated by CMR-feature tracking for primary analysis with a global longitudinal strain threshold of 20% used to define impaired RV strain (RVIS); secondary functional analysis via RV ejection fraction was also performed. RESULTS: A total of 2604 patients were studied, among whom RVIS was present in 461 patients (18%). The presence and magnitude of RVIS were strongly associated with LV dysfunction, irrespective of whether measured by LV ejection fraction or wall motion score (P<0.001 for all). Regarding tissue substrate, regions of ischemic and dysfunctional myocardium (ie, hibernating myocardium) and infarct size were each independently associated with RVIS (both P<0.001). During follow-up (median, 4.62 [interquartile range, 2.15-7.67] years), 555 deaths (21%) occurred. Kaplan-Meier analysis for patients stratified by presence and magnitude of RV dysfunction by global longitudinal strain and RV ejection fraction each demonstrated strong prognostic utility for all-cause mortality (P<0.001). RVIS conferred increased mortality risk (hazard ratio, 1.35 [95% CI, 1.11-1.66]; P=0.003) even after controlling for LV function, infarction, and ischemia. CONCLUSIONS: RVIS in patients with known coronary artery disease is associated with potentially reversible LV processes, including LV functional impairment due to ischemic and predominantly viable myocardium, which confers increased mortality risk independent of LV function and tissue substrate.
Subject(s)
Coronary Artery Disease , Magnetic Resonance Imaging, Cine , Myocardial Perfusion Imaging , Ventricular Dysfunction, Right , Ventricular Function, Right , Humans , Male , Female , Coronary Artery Disease/physiopathology , Coronary Artery Disease/complications , Coronary Artery Disease/diagnostic imaging , Middle Aged , Aged , Magnetic Resonance Imaging, Cine/methods , Ventricular Dysfunction, Right/physiopathology , Ventricular Dysfunction, Right/etiology , Ventricular Dysfunction, Right/diagnostic imaging , Ventricular Function, Right/physiology , Myocardial Perfusion Imaging/methods , Predictive Value of Tests , Stroke Volume/physiology , Ventricular Function, Left/physiology , Prognosis , United States/epidemiologyABSTRACT
Background: Severe mitral regurgitation is a progressive disease associated with high morbidity and mortality, and frequent readmissions for heart failure. Surgical mitral valve repair or replacement has been the gold-standard treatment; however, advances in transcatheter edge-to-edge repair (TEER) have provided alternatives for high-risk surgical patients. There are no data on racial disparities in access to high-volume TEER centers. Methods: Data on TEER hospitalizations from New York, New Jersey, Maryland, North Carolina, Washington, Colorado, Arizona, and Florida were analyzed using the State Inpatient Databases for 2016. The baseline characteristics of patients who underwent TEER at high- (≥25 procedures per year) and low-volume centers were identified. The association between race and the likelihood of undergoing TEER at high-volume centers was assessed. The secondary outcomes were mortality and the frequency of home discharges. Results: Of 1567 patients included in the analysis, 1129 underwent TEER at high-volume centers. Patients treated at high-volume centers had a higher prevalence of chronic kidney disease and congestive heart failure. Black and Hispanic patients were 59% (adjusted odds ratio [OR], 0.41; P < .001) and 51% (adjusted OR, 0.49; P < .001) less likely to undergo TEER at high-volume centers, respectively, compared with White patients. Hispanic patients were 3 times more likely to die during index admission than White patients (adjusted OR, 3.32; P = .027). There was geographic clustering of TEER centers, and a higher ratio of White patients to minority patients in zip codes with high-volume TEER centers. Conclusions: Racial minorities patients, particularly Black and Hispanic patients, are less likely to undergo TEER at high-volume centers. Hispanic patients experience higher rates of in-hospital mortality after TEER than White patients.