Abstract 10506: Risk and Benefit of Coronary Reactivity Testing in Women with No Obstructive Coronary Artery Disease: The NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study
Background: Microvascular coronary dysfunction (MCD) in women with no obstructive coronary artery disease (CAD) portends an adverse prognosis of an overall 2.5% annual major adverse cardiovascular event (MACE) rate. The diagnosis of MCD is established by invasive coronary reactivity testing (CRT), yet the risk of CRT in contemporary interventional labs among this population is unknown.
Methods: We evaluated 330 women who had clinical evidence of ischemia, no obstructive CAD by angiography (<50% stenosis in any epicardial vessel), and underwent CRT at two experienced centers. Microvascular function was assessed using a Doppler flow wire (FloWire® Volcano) in a proximal left coronary artery. Coronary flow reserve was measured after intracoronary (IC) adenosine injections (18 and 36 mcg). Increasing doses of IC acetylcholine (0.364 mcg and 36.4 mcg infused over 3 min) were used to assess endothelial function. IC nitroglycerin (NTG, 200 mcg) was used to assess smooth muscle function and determine maximal dilatory capacity. CRT-related serious adverse events (SAE) and adverse events (AE) were recorded. For comparison, follow-up MACE included death, nonfatal myocardial infarction (MI), nonfatal stroke, or hospitalization for heart failure.
Results: Mean age was 54 ± 10 yrs, and 82% were Caucasian. During and immediately following CRT-SAEs occurred in 2 women (0.6 %): 1 coronary artery dissection (0.3%) and 1 ST-elevation MI related to coronary artery spasm (0.3%) and neither resulted in permanent sequelae. CRT-AEs occurred in 4 women (1.2 %): 1 had transient air microembolism (0.3%), 2 had coronary spasm requiring NTG (0.6%), and 1 developed deep venous thrombosis in leg used for groin access (0.3%). There was no CRT-related mortality. In 4.2 years follow-up period, 48 women experienced MACE events among those with MCD: 11 died (3.3%), 9 had non-fatal MIs (2.7%), 10 had nonfatal strokes (3.0%), and 18 were hospitalized for heart failure (5.5%).
Conclusions: In women undergoing CRT for suspected MCD, contemporary testing appears relatively low risk compared to the MACE rate observed in follow up after diagnosis of MCD. These results support the use of CRT by experienced interventional operators for diagnostic and prognostic benefit in this at risk population.
- © 2011 by American Heart Association, Inc.