Prasad, Abhiram

Background Soluble urokinase plasminogen activator receptor (su PAR ) is a proinflammatory biomarker associated with immune activation and fibrinolysis inhibition. Plasminogen activator inhibitor ( PAI ‐1) is associated with excessive fibrin accumulation, thrombus formation, and atherosclerosis. The relationship between cross‐coronary su PAR and PAI ‐1 production and endothelial dysfunction remains unknown. Methods and Results Seventy‐nine patients (age 53±10 years, 75% women) with angina and normal coronary arteries or mild coronary artery disease (<40% stenosis) on angiogram underwent acetylcholine assessment of epicardial endothelial dysfunction (mid–left anterior descending coronary artery diameter decrease >20% after acetylcholine) and mircovascular endothelial dysfunction (coronary blood flow change <50% after acetylcholine). Simultaneous left main and coronary sinus su PAR and PAI ‐1 levels were measured in each patient before acetylcholine administration, and cross‐coronary su PAR and PAI ‐1 production rates were calculated. Patients’ characteristics, except for age (51±10 versus 57±9, P =0.02), and resting coronary hemodynamics were not significantly different between patients with (26%) versus without (74%) epicardial endothelial dysfunction. Patients’ characteristics and resting coronary hemodynamics were not significantly different between those with (62%) and those without (38%) mircovascular endothelial dysfunction. Patients with mircovascular endothelial dysfunction demonstrated local coronary su PAR production versus su PAR extraction in patients with normal microvascular function (median 25.8 [interquartile range 121.6, −23.7] versus −12.7 [52.0, −74.8] ng/min, P =0.03). Patients with epicardial endothelial dysfunction had higher median coronary PAI ‐1 production rates compared with those with normal epicardial endothelial function (1224.7 [12 940.7, −1915.4] versus −187.4 [4444.7, −4535.8] ng/min, P =0.03). Conclusions su PAR is released in coronary circulation of patients with mircovascular endothelial dysfunction and extracted in those with normal microvascular function. Cross‐coronary PAI ‐1 release is higher in humans with epicardial endothelial dysfunction.

Objectives: To investigate the role of endothelial function in patients with previous spontaneous coronary artery dissection. Background: Mechanisms underlying spontaneous coronary artery dissection, including a possible contribution from endothelial dysfunction, remain poorly understood. Methods: This was a single center, retrospective study of patients with a prior spontaneous coronary artery dissection episode who underwent invasive endothelial function testing in the cardiac catheterization laboratory for evaluation of recurrent chest pain. Coronary epicardial and microvascular responses to acetylcholine, adenosine, and nitroglycerine were assessed. Findings were compared to a reference group of normal controls ( n=232). Results: A total of 10 patients with prior angiographically confirmed spontaneous coronary artery dissection were referred for coronary endothelial function testing. The median coronary flow reserve was 2.8 (interquartile range (IQR) 2.3, 3.6). The median change in coronary diameter with acetylcholine was −0.9% (IQR −23.9, 4.2). The median increase in peak coronary blood flow following acetylcholine administration was 91.4% (IQR 9.1, 105.7), which was similar to the response observed in a reference group of patients (median age 51 years, 96% women) from our laboratory with normal microvascular responses to acetylcholine: 107.4% (IQR 75.5, 165.7; P=0.20). Four patients (40%) had an abnormal microvascular response to acetylcholine, with less than a 50% increase in coronary blood flow, and all but one patient had left anterior descending artery or multivessel spontaneous coronary artery dissection. Conclusion: Coronary epicardial and microvascular vasomotor dysfunction is not a predominant feature of spontaneous coronary artery dissection. Endothelial dysfunction is not implicated as the principal underlying mechanism.

Background— Women have higher rates of all-cause mortality after percutaneous coronary intervention. Whether this is because of greater age and comorbidity burden or a sex-specific factor remains unclear. Methods and Results— We retrospectively assessed cause-specific long-term mortality after index percutaneous coronary intervention over 3 time periods (1991–1997, 1998–2005, and 2006–2012). Cause of death was determined using telephone interviews, medical records, and death certificates. We performed competing risks analyses of cause-specific mortality. A total of 6847 women and 16 280 men survived index percutaneous coronary intervention hospitalization 1991 to 2012. Women were older (mean±SD: 69.4±12 versus 64.8±11.7 years; P <0.001) with more comorbidities (mean±SD: Charlson index 2.1±2.1 versus 1.9±2.1; P <0.001). Across the 3 time periods, both sexes exhibited a decline in cardiac deaths at 5 years (26% relative decrease in women, 17% in men, trend P <0.001 for each). Although women had higher all-cause mortality compared with men in all eras, the excess mortality was because of noncardiac deaths. In the contemporary era, only a minority of deaths were cardiac (33.8% in women, 38.0% in men). After adjustment, there was no evidence for a sex-specific excess of risk for cardiac or noncardiac mortality. The commonest causes of death were chronic diseases and heart failure in women (5-year cumulative mortality, 5.4% and 3.9%) but cancer and myocardial infarction/sudden death in men (5.4% and 4.3%). Conclusions— The higher mortality after percutaneous coronary intervention in women is because of death from noncardiac causes. This is accounted for by baseline age and comorbidities rather than an additional sex-specific factor. These findings have implications for sex-specific clinical care and trial design.

Background and aim Thoracic radiation therapy (XRT) for cancer is associated with the development of significant coronary artery disease that may require coronary artery bypass grafting surgery (CABG). Contemporary acute surgical outcomes and long-term postoperative survival of patients with prior XRT have not been well characterised. Methods This was a retrospective, single-centre study of patients with a history of thoracic XRT who required CABG and who were propensity matched against 141 controls who underwent CABG over the same time period. The objectives were to assess early CABG outcomes and long-term survival in patients with prior XRT. Results Thirty-eight patients with a history of previous thoracic XRT underwent CABG from 1994 to 2013. The median time from XRT exposure to surgery was 7.9 years (IQR: 2.5–18.4 years). Perioperative adverse events were similar in the XRT group and controls; however, there was a trends lower utilisation of internal mammary artery (IMA) grafts in the XRT group (89%vs98%, P=0.13). After a median postoperative follow-up of 5.4 years (IQR 0.9–9.4 years), no difference in long-term all-cause mortality was observed. Conclusion Patients with prior thoracic XRT who undergo CABG have similar long-term all-cause mortality compared with controls. Isolated CABG after thoracic XRT is not associated with higher perioperative complications, but IMA graft use may be limited by prior XRT.

Background Participation in cardiac rehabilitation ( CR ) is an essential component of care for patients with coronary artery disease. However, little is known about its benefit on cardiovascular outcomes in patients with diabetes mellitus ( DM ) who have undergone percutaneous coronary intervention. The aim of our study was to evaluate the impact of CR in this high‐risk group of patients. Methods and Results We performed a retrospective analysis of all patients with DM who underwent percutaneous coronary intervention in Olmsted County (Minnesota) between 1994 and 2010, assessing the impact of CR participation on clinical outcomes. CR participation was significantly lower in patients with DM (38%, 263/700) compared with those who did not have DM (45%, 1071/2379; P =0.004). Using propensity score adjustment, we found that in patients with DM , CR participation was associated with significantly reduced all‐cause mortality (hazard ratio, 0.56; 95% confidence interval, 0.39–0.80; P =0.002) and composite end point of mortality, myocardial infarction, or revascularization (hazard ratio, 0.77; 95% confidence interval, 0.60–0.98; P =0.037), during a median follow‐up of 8.1 years. In patients without DM , CR participation was associated with a significant reduction in all‐cause mortality (hazard ratio, 0.67; 95% confidence interval, 0.55–0.82; P <0.001) and cardiac mortality (hazard ratio, 0.67; 95% confidence interval, 0.47–0.95; P =0.024). Conclusions CR participation after percutaneous coronary intervention is associated with lower all‐cause mortality rates in patients with DM , to a similar degree as for those without DM . However, CR participation was lower in patients with DM , suggesting the need to identify and correct the barriers to CR participation for this higher‐risk group of patients.

We present the case of a 61-year-old woman admitted with chest pain and an ECG demonstrating ST-segment elevation in the lateral leads. Emergency coronary angiography demonstrated an occluded obtuse marginal branch. Percutaneous intervention was unsuccessful as the lesion could not be crossed with a wire. Left ventriculography and transthoracic echocardiography demonstrated hypokinesis of the entire apex but preserved contractility of the basal segments, consistent with a diagnosis of apical ballooning syndrome (ABS). Cardiac MRI demonstrated myocardial oedema in all mid to apical segments, with a left ventricular ejection fraction (LVEF) of 38%. Repeat study at 5 months demonstrated an infarct in the distribution of the occluded artery with late gadolinium enhancement, consistent with a diagnosis of a lateral wall myocardial infarction and an improvement in the LVEF to 51%. The case illustrates the novel observation that ABS and acute myocardial infarction may rarely occur simultaneously.

Objectives Percutaneous coronary intervention (PCI) for acute coronary syndromes frequently fails to restore myocardial perfusion despite establishing epicardial vessel patency. Endothelin-1 (ET-1) is a potent vasoconstrictor, and its expression is increased in atherosclerosis and after PCI. In this study, we aim to define the role of endothelin in regulating coronary microvascular blood flow and myocardial perfusion following PCI in patients with non-ST elevation acute coronary syndromes (NSTACS), by assessing whether adjunctive therapy with a selective endothelin A (ETA) receptor antagonist acutely improves postprocedural coronary microvascular blood flow. Methods In a randomised, double-blinded, placebo-controlled trial, 23 NSTACS patients were enrolled to receive an intracoronary infusion of placebo (n=11) or BQ-123 (n=12) immediately before PCI. Post-PCI coronary microvascular blood flow and myocardial perfusion were assessed by measuring Doppler-derived average peak velocity (APV), and cardiac biomarker levels were quantified. Results Compared with the placebo group, APV was significantly higher in the drug group immediately after PCI (30 (20, 37) vs 19 (9, 26) cm/s; p=0.03). Hyperaemic APV, measured post-adenosine administration, was higher in the BQ-123 group, but the difference did not achieve statistical significance (56 (48, 72) vs 46 (34, 64) cm/s; p=0.090). Maximum coronary flow reserve postprocedure was not different between the two groups (2.1 (1.6, 2.3) vs 2.5 (1.8, 3.0)). Per cent change in creatine kinase isoenzyme MB from the time of PCI to 8 and 16 hours post-PCI was significantly lower in the drug group compared with the placebo group (−17 (−26, −10) vs 26 (−15, 134); p=0.02 and −17 (−38, 14) vs 107 (2, 446); p=0.007, respectively). Conclusions Endothelin is a mediator of microvascular dysfunction during PCI in NSTACS, and adjunctive selective ETA antagonist may augment myocardial perfusion during PCI. Trial registration number NCT00586820; Results.