Prasad, Abhiram

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.

Background— Current risk models for predicting long-term mortality after percutaneous coronary intervention are restricted to all-cause mortality. We sought to develop novel risk models for the prediction of cardiac and noncardiac mortality after percutaneous coronary intervention. Methods and Results— We retrospectively evaluated patients who underwent index percutaneous coronary intervention at Mayo Clinic from 2003 to 2008. Long-term deaths were ascertained through scheduled prospective surveillance. Cause of death was determined via telephone interviews, medical records, and autopsy reports. Fine and Gray extension of Cox proportional hazards models was used to model cause-specific cumulative incidence. Candidate variables and interactions were chosen a priori, without variable selection methods. Resulting models were mapped to an integer-based risk score. The study comprised 6636 patients followed up over a median of 62 months (25th, 75th percentiles: 45, 77 months). There were 1488 deaths, 518 (35%) cardiac, 938 (63%) noncardiac, and 32 (2%) unknown. The 5-year predicted cardiac mortality ranged from 0.6% to 97%, with a corrected c -statistic of 0.82. Risk factors for cardiac death included age, body mass index, ejection fraction, and history of congestive heart failure. The integer score for noncardiac death included age, medicine index, body mass index, current smoker, noncardiac Charlson index and cardiac Charlson index, and accommodated significant age-based interactions for smoking and the 2 Charlson indices. Predicted noncardiac mortality at 5 years ranged from 0.2% to 81%, with a corrected c -statistic of 0.77. Conclusions— We report novel risk models to predict cardiac and noncardiac long-term mortality after percutaneous coronary intervention.

Objective There is a paucity of data on the impact of complete revascularisation (CR) following percutaneous coronary intervention (PCI) among patients with diabetes with multivessel coronary disease. In this study, we assess the impact of CR, using a relatively simple anatomical definition, on long-term outcomes (median follow-up 7.9 years) in patients with diabetes, and compare with patients without diabetes. Methods 5350 patients with multivessel disease (coronary stenoses ≥70% in ≥2 major epicardial arteries) who underwent PCI between January 1997 and June 2011 were included. Patients were divided into 4 groups according to diabetes and CR status (absence of residual coronary stenosis in major, predominantly proximal, epicardial segments according to Coronary Artery Surgery Study (CASS) classification). Results Patients with diabetes and patients with incomplete revascularisation (IR) had more adverse clinical and angiographic characteristics. IR was frequent in patients with diabetes, and was marginally more common than in patients without diabetes (47% vs 44%, p<0.001). Patients with diabetes and patients without diabetes had higher mortality rates after IR than after CR (HR 1.56 (95% CI (1.39 to 1.85), p<0.001 for patients with diabetes and 1.70 (95% CI (1.50 to 1.92), p<0.001) in patients without diabetes). However, the absolute risk was higher for patients with diabetes (5-year mortality: IR 35.8%, CR 21.2%) than in patients without diabetes (5-year mortality: IR 22.2%, CR 14.1%). In a multivariable model, IR and diabetes mellitus were independent predictors of total mortality. This effect was present in the bare metal stent and drug-eluting stent eras and in patients with stable disease and acute coronary syndromes. Conclusions CR is associated with lower long-term mortality in patients with diabetes and patients without diabetes. However the difference was significantly greater in patients with diabetes compared with patients without diabetes.

Background Survivors of ventricular fibrillation out of hospital cardiac arrest ( VF ‐ OHCA ) due to a potentially reversible cause such as acute myocardial infarction (MI) or ischemia are considered to be at low risk of recurrent arrhythmia. Implantable cardioverter defibrillators ( ICD ) are not routinely recommended in such patients. However, the outcome of these patients in the era of rapid coronary revascularization and ICD therapy is not known. Methods and Results We examined the outcome of 114 consecutive survivors of VF OHCA due to acute MI or ischemia in Olmsted County, MN from 1990 to 2011. An ICD was implanted in 45/114 patients. ICD recipients had lower EF [median ( IQR ) 38 (26 to 54) versus 48 (35 to 58) %, P =0.04]. During a median ( IQR ) follow‐up of 9.9 (4.4 to 14.6) years, ICD implantation was associated with reduced cardiac mortality ( HR 0.24 [0.07 to 0.88], P =0.031) and a trend towards reduced all‐cause mortality ( HR 0.56 [0.30 to 1.02], P =0.059) after adjusting for the first principal component. One or more appropriate ICD therapies were delivered in 19/45, with half of the patients receiving therapy within 1 year. Patients with EF ≤35% at discharge continued to be at long‐term risk for ICD therapy compared with those with EF >35% who were at increased risk predominantly in the first 8 months. EF and revascularization were not significantly associated with ICD therapy in the multivariable analysis. Conclusions Patients with VF ‐ OHCA in the setting of acute MI or myocardial ischemia remain at high risk of recurrent ventricular arrhythmias, particularly if EF ≤35%. This suggests that ICD implantation may be reasonable if EF ≤35%.

Objectives: To retrospectively evaluate outcomes among cancer survivors previously treated with thoracic radiotherapy (RT) who later underwent percutaneous coronary intervention (PCI). Methods: From 1998 to 2012, 76 patients first received curative RT (>30 Gy, except for Hodgkin lymphoma patients) involving the heart and lungs followed by PCI. Heart and lung–specific dosimetric parameters were correlated with overall survival (OS) and cardiac-specific survival by Cox variate methods. Results: The mean interval between cancer diagnosis and PCI was 3.7 years (range, 0.1 to 12.6 y). Median follow-up since cancer diagnosis was 5.5 years. At analysis, 46 patients (61%) were alive, 5 (7%) died of cardiac causes, and 9 (12%) of cancer. Higher maximum RT heart dose was related to poorer OS since PCI (P=0.009). Angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (P=0.005) and higher mean heart dose (P<0.001) were related to poorer OS since cancer diagnosis. β-Blockers, higher mean heart dose (hazard ratio [HR]=1.49, P<0.001), and percentage of targeted volume or organ receiving ≥40 Gy for heart doses (HR=1.32, P<0.001) were associated with poorer non–cancer-specific survival since cancer diagnosis. Diabetes (HR=3.84, P=0.008) and increased percentage of targeted volume or organ receiving ≥45 Gy (HR=1.01 per additional 100 cm3 irradiated, P=0.01) for the heart decreased major adverse cardiac event–free survival. Conclusions: Prior heart and lung–directed RT had volume-dependent and dose-dependent adverse effects on long-term cardiac outcomes for patients subsequently treated with PCI. RT planning that minimizes heart and lung irradiation doses should be encouraged.

Objective— Endothelial dysfunction is an early manifestation of atherosclerosis. Inflammation and vasa vasorum play a pivotal role in the pathophysiology of plaque initiation, development, and complications. Optical coherence tomography allows high-resolution imaging of tissue microstructure. Therefore, the aim of this study was to test the hypothesis that segments with endothelial dysfunction show macrophages and vasa vasorum in patients with early coronary artery disease. Approach and Results— Optical coherence tomography images were obtained from 40 patients with mild coronary atherosclerosis who underwent coronary endothelial function assessment. Optical coherence tomography findings, including macrophages and microchannels, were evaluated in 76 coronary segments corresponding to those in endothelial response to acetylcholine. Coronary artery diameter change in response to acetylcholine was more severe in segments showing macrophages (−17.7±14.7% versus −6.3±13.9%; P <0.01) and microchannels (−15.9±15.9% versus −6.4±13.5%; P <0.01) than those without. There were increasing trends of the prevalence of macrophages and microchannels with endothelial dysfunction as stratified by quartiles of coronary artery diameter change ( P <0.01 and P =0.02 for trend, respectively). In particular, segments with both macrophages and microchannels (n=12) tended to have worse endothelial function than those with macrophages alone (n=15) and microchannels alone (n=15; −22.1±14.6% versus −10.9±15.6% and −10.9±15.6%; P =0.07 and P =0.06, respectively). Conclusions— Epicardial endothelial dysfunction was associated with optical coherence tomography –identified macrophages and microchannels in mild coronary atherosclerosis. The current study further supports the role of inflammation and vasa vasorum proliferation in the early stage of coronary atherosclerosis.