Citations

Background: Spontaneous coronary artery dissection (SCAD) is an uncommon idiopathic disorder predominantly affecting young, otherwise healthy women. Rare familial cases reveal a genetic predisposition to disease. The aim of this study was to identify a novel susceptibility gene for SCAD. Methods: Whole-exome sequencing was performed in a family comprised of 3 affected individuals and filtered to identify rare, predicted deleterious, segregating variants. Immunohistochemical staining was used to evaluate protein expression of the identified candidate gene. The prevalence and spectrum of rare (<0.1%) variants within binding domains was determined by next-generation sequencing or denaturing high-performance liquid chromatography in a sporadic SCAD cohort of 675 unrelated individuals. Results: We identified a rare heterozygous missense variant within a highly conserved β-integrin–binding domain of TLN1 segregating with familial SCAD. TLN1 encodes talin 1—a large cytoplasmic protein of the integrin adhesion complex that links the actin cytoskeleton and extracellular matrix. Consistent with high mRNA expression in arterial tissues, robust immunohistochemical staining of talin 1 was demonstrated in coronary arteries. Nine additional rare heterozygous missense variants in TLN1 were identified in 10 sporadic cases. Incomplete penetrance, suggesting genetic or environmental modifiers of this episodic disorder, was evident in the familial case and 5 individuals with sporadic SCAD from whom parental DNA was available. Conclusions: Our findings reveal TLN1 as a disease-associated gene in familial and sporadic SCAD and, together with abnormal vascular phenotypes reported in animal models of talin 1 disruption, implicate impaired structural integrity of the coronary artery cytoskeleton in SCAD susceptibility.

Objective— Coronary endothelial dysfunction (ED) is an early stage of atherosclerosis and is associated with impaired high-density lipoprotein (HDL) function. A functional polymorphism at the haptoglobin (Hp) gene locus (rs72294371) has been associated with marked differences in HDL structure and function. We sought to determine whether Hp phenotype was associated with coronary ED and whether the amount of hemoglobin (Hb) tethered to HDL via Hp was Hp-type dependent and associated with ED. Approach and Results— Microvascular and epicardial coronary endothelial function was assessed in 338 individuals with nonobstructive coronary artery disease. Microvascular ED was defined as <50% change in coronary blood flow and epicardial ED as ≥20% decrease in coronary artery diameter after intracoronary acetylcholine infusion. The amount of Hb bound to HDL was measured by ELISA after HDL purification from plasma samples using immune-affinity chromatography. One hundred and seventy of the individuals in this study (50.3%) were diagnosed with microvascular ED, 143 (42.3%) with epicardial ED, and 67 (19.7%) had diabetes mellitus (DM). Hp phenotype was significantly associated with microvascular ( P =0.01) and epicardial ED ( P =0.04) among DM individuals. There was a significant and inverse correlation between the amount of HDL-bound Hb and change in coronary blood flow (r=−0.40; P <0.0001) and in coronary artery diameter (r=−0.44; P <0.0001) in response to acetylcholine infusion. Hb content of HDL was significantly increased in individuals with Hp 2-2 and DM. In a logistic regression model, Hp 2-2 phenotype was associated with microvascular ED (odds ratio, 1.9; P =0.03) and the amount of HDL-bound Hb was an independent predictor of both microvascular (odds ratio, 4.6 for each 1-SD increase; P <0.0001) and epicardial (odds ratio, 2.2; P <0.0001) ED. Conclusions— Hp phenotype is significantly associated with coronary ED in DM individuals. This association is likely related to increased Hb tethering to HDL via Hp 2-2 in DM.

Aim Angina pectoris in the absence of obstructive coronary artery disease (CAD) is common and is associated with poor quality of life (QOL). Coronary microvascular endothelial dysfunction is associated with myocardial ischaemia and is a common cause of angina. We hypothesise that evaluation of coronary endothelial function, its diagnosis and treatment will favourably impact QOL in patients with angina symptoms and non-obstructive CAD. Methods and results Follow-up was done on 457 patients with chest pain and non-obstructive coronary arteries who had undergone coronary vascular reactivity evaluation by administration of intracoronary acetylcholine at the time of diagnostic study. After a mean follow-up of 8.4±4.7 years, QOL was assessed by administration of the SF-36 QOL survey. Patients diagnosed and treated for microvascular endothelial dysfunction had a higher (better) overall mental composite score (44.8 vs 40.9, p=0.036) and mental health score (44.2 vs 40.7, p=0.047), and a trend towards higher vitality scores (39.1 vs 35.9, p=0.053) and role emotional scores (43.6 vs 40.4, p=0.073), compared with patients with normal endothelial function. Conclusion Among patients with chest pain and normal coronaries, diagnosis and treatment of coronary microvascular endothelial dysfunction in those with angina pectoris and non-obstructive CAD are associated with better QOL compared with patients with normal endothelial function.

Background There are limited data on the role of temporary mechanical circulatory support ( MCS ) devices for cardiogenic shock before left ventricular assist device ( LVAD ) surgery. This study sought to evaluate the trends of use and outcomes of MCS in cardiogenic shock before LVAD surgery. Methods and Results This was a retrospective cohort study from 2005 to 2014 using the National Inpatient Sample (20% stratified sample of US hospitals). This study identified admissions undergoing LVAD surgery with preoperative cardiogenic shock. Admissions for other cardiac surgery and heart transplant were excluded. Temporary MCS was identified using administrative codes. The primary outcome was hospital mortality and secondary outcomes were hospital costs and lengths of stay in admissions with and without MCS use. In this 10‐year period, 9753 admissions were identified with 40.6% requiring pre‐ LVAD MCS . There was a temporal increase in the frequency of cardiogenic shock associated with an increase in non–intra‐aortic balloon pump MCS devices. The cohort receiving MCS had greater in‐hospital myocardial infarction, ventricular arrhythmias, and use of coronary angiography. On multivariable analysis, older age, myocardial infarction, and need for MCS devices were independently predictive of higher in‐hospital mortality. In 696 propensity‐matched pairs, use of MCS was predictive of higher in‐hospital mortality (odds ratio 1.4 [95% confidence interval 1.1–1.6]; P =0.02) and higher hospital costs, but similar lengths of stay. Conclusions In patients with cardiogenic shock bridged to LVAD therapy, there was a steady increase in preoperative MCS use. Use of MCS identified patients at higher risk for in‐hospital mortality and greater resource utilization.

Background Spontaneous coronary artery dissection (SCAD) is a cause of acute coronary syndrome predominantly in women without usual cardiovascular risk factors. Many have a history of migraine headaches, but this association is poorly understood. This study aimed to determine migraine prevalence among SCAD patients and assess differences in clinical factors based on migraine history. Methods and Results A cohort study was conducted using the Mayo Clinic SCAD “Virtual” Multi‐Center Registry composed of patients with SCAD as confirmed on coronary angiography. Participant‐provided data and records were reviewed for migraine history, risk factors, SCAD details, therapies, and outcomes. Among 585 patients (96% women), 236 had migraine history; the lifetime and 1‐year prevalence of migraine were 40% and 26%, respectively. Migraine was more common in SCAD women than comparable literature‐reported female populations (42% versus 24%, P <0.0001; 42% versus 33%, P <0.0001). Among all SCAD patients, those with migraine history were more likely to be female (99.6% versus 94%; P =0.0002); have SCAD at a younger age (45.2±9.0 years versus 47.6±9.9 years; P =0.0027); have depression (27% versus 17%; P =0.025); have recurrent post‐SCAD chest pain at 1 month (50% versus 39%; P =0.035); and, among those assessed, have aneurysms, pseudoaneurysms, or dissections (28% versus 18%; P =0.018). There was no difference in recurrent SCAD at 5 years for those with versus without migraine (15% versus 19%; P =0.39). Conclusions Many SCAD patients have a history of migraine. SCAD patients with migraine are younger at the time of SCAD; have more aneurysms, pseudoaneurysms, and dissections among those imaged; and more often report a history of depression and post‐SCAD chest pain. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifiers: NCT01429727, NCT01427179.

Background: Risks and mechanisms of extension of conservatively managed spontaneous coronary artery dissection (SCAD) remain incompletely understood. Study objectives were to (1) evaluate mechanisms of early SCAD evolution through serial angiographic analysis, and (2) determine predictors of early SCAD progression. Methods and Results: Retrospective registry study of patients with SCAD managed with an initial conservative strategy (n=240). Patients who experienced significant SCAD progression within 14 days, defined as clinical worsening plus new critical coronary obstruction on repeat angiography, were compared with remaining controls. A total of 42 of 240 (17.5%) experienced significant SCAD progression after index conservative approach; 91% by day 6. Isolated intramural hematoma (IMH) at baseline (no intimal dissection) was observed more frequently in those experiencing progression compared with controls (69.1% versus 44.4%; P =0.004). Multivariable predictors of SCAD progression included lesion severity, multivessel involvement, and isolated IMH. To investigate mechanisms of SCAD evolution, all repeat angiograms ≤14 days were compared with corresponding baselines (n=82 patient angiogram pairs). Of those with isolated IMH at baseline, 20% developed intimal dissection at repeat study. IMH was associated with greater longitudinal lesion extension (11.5 versus 2.8 mm; P =0.01), worsening Thrombolysis in Myocardial Infarction flow (−0.8 versus 0.1; P =0.003), and a nonsignificant lower rate of angiographic improvement (20.0% versus 31.3%; P =0.16) compared with the group with baseline intimal dissection. Optical coherence tomography subgroup analysis (n=17) indicated intimo-medial thickness to be lowest at the midpoint of IMH. Conclusions: Conservatively managed SCAD carries a 1:6 hazard for serious deterioration within 6 days. The risk was higher in those with isolated IMH at baseline. IMH often precedes development of intimal dissection, which has implications for mechanisms of SCAD.

BACKGROUND: Noncardiac surgery (NCS) following percutaneous coronary intervention (PCI) with stenting is sometimes associated with major adverse cardiac events (MACEs). Second-generation drug-eluting stents (DES) were developed to decrease the incidence of MACE seen with bare metal and first-generation DES. METHODS: The medical records of all adult patients who underwent second-generation DES placement between July 29, 2008 and July 28, 2011 followed by NCS between September 22, 2008 and July 1, 2013 were reviewed. All episodes of MACE following surgery were recorded. RESULTS: A total of 282 patients (74.8% male) were identified who underwent NCS after PCI with second-generation DES. MACE occurred in 15 patients (5.3%), including 11 deaths. The incidence of MACE changed significantly with time from PCI to NCS: 17.1%, 10.0%, 0.0%, and 3.1% for patients undergoing NCS at 0–90, 91–180, 181–365, and ≥366 days, respectively. Compared with those having NCS ≥366 days after PCI, the odds ratio for MACE (95% confidence interval) was 6.4 (1.9 to 21.3) at 0–90 days and 3.4 (0.8 to 15.3) at 91–180 days. Seven days prior to NCS, 146 (52%) patients were on dual antiplatelet therapy (DAPT), 106 (38%) were on aspirin, and 30 (11%) did not receive antiplatelet therapy. Excessive surgical bleeding occurred in 19 cases (6.7%). While observed bleeding rates were lowest in those not receiving antiplatelet therapy, there were no statistically significant differences based on the presence or absence of antiplatelet therapy (3% [1/30] for no antiplatelet therapy compared to 6% [6/106] for aspirin monotherapy and 8% [12/146] for DAPT; Fisher exact test: P = .655). CONCLUSIONS: The incidence of MACE in patients with second-generation DES undergoing NCS was 5.3% and was highest in the first 180 days following DES implantation. The rate of excessive surgical bleeding was 6.7% with the highest observed rate in those on DAPT. However, differences by the presence or absence of antiplatelet therapy were not significant, and future large observational studies will be necessary to further define bleeding risk with continued DAPT.

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.