Key result
Microvascular angina was associated with diminished coronary flow reserve compared to healthy controls (2.41 vs 3.35; P<.03), and impaired right ventricular mechanics correlated with reduced exercise capacity.
Why the study?
The study was conducted to assess right ventricular mechanics in patients with microvascular angina and examine their association with coronary flow reserve and exercise tolerance.
Observational (n=101)
In patients with microvascular angina, impaired right ventricular mechanics assessed by speckle tracking imaging correlate with reduced coronary flow reserve and exercise capacity.
OBJECTIVES: We planned to assess the right ventricular mechanics in subjects with typical chest pain and angiographically normal coronary arteries (microvascular angina [MVA]) and to search for an association between right ventricular mechanics, coronary flow reserve, and exercise tolerance. METHODS: Seventy-one patients with MVA (mean age of 48.5 ± 7.9 years, 63% female) and 30 healthy control subjects were recruited. Right ventricular mechanics were calculated utilizing speckle tracking imaging. The exercise capacity was assessed by metabolic equivalents (METs). Coronary flow reserve (CFR) was calculated as the ratio between hyperemic (in response to intravenous adenosine) diastolic peak flow velocity and the basal diastolic peak velocity. RESULTS: Coronary flow reserve (a surrogate marker of microvascular dysfunction) was diminished in MVA patients compared with the control group (2.41 ± 0.35 vs 3.35 ± 0.5; P < .03). Patients with lower right ventricular global longitudinal strain (RVGLS) and right ventricular global longitudinal strain rate (RVGLSr) had a considerably lower CFR (P < .001) and a significantly lower MET (P < .001) than patients with normal RV mechanics. Right ventricular global longitudinal strain and RVGLSr were significantly correlated with both CFR and METs in subjects with MVA. Receiver operating characteristic (ROC) curve analysis demonstrated that RVGLS ≤ -14.5 was the best cutoff value for the prediction of impaired exercise tolerance in patients with MVA. CONCLUSION: We suggested that impaired right ventricular mechanics in subjects with microvascular angina was associated with reduced exercise capacity. Moreover, right ventricular mechanics is significantly correlated with coronary flow reserve. Henceforth, right ventricular mechanics might be of value for both risk stratification and follow-up in cases with microvascular dysfunction.
No takes yet. Share an insight, caveat, or question.
Mahfouz et al. (2019) conducted an observational in Microvascular angina (n=101). Microvascular angina vs. Healthy controls was evaluated on Coronary flow reserve (p=<.03). Microvascular angina was associated with diminished coronary flow reserve compared to healthy controls (2.41 vs 3.35; P<.03), and impaired right ventricular mechanics correlated with reduced exercise capacity.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: