Tara Sedlak

Spontaneous Coronary Artery Dissection Association With Predisposing Arteriopathies and Precipitating Stressors and Cardiovascular Outcomes

Background—Nonatherosclerotic spontaneous coronary artery dissection (NA-SCAD) is underdiagnosed and an important cause of myocardial infarction in young women. The frequency of predisposing and precipitating conditions and cardiovascular outcomes remains poorly described. Methods and Results—Patients with NA-SCAD prospectively evaluated (retrospectively or prospectively identified) at Vancouver General Hospital were included. Angiographic SCAD diagnosis was confirmed by 2 experienced interventional cardiologists and categorized as type 1 (multiple lumen), 2 (diffuse stenosis), or 3 (mimic atherosclerosis). Fibromuscular dysplasia screening of renal, iliac, and cerebrovascular arteries were performed with angiography or computed tomographic angiography/MR angiography. Baseline, predisposing and precipitating conditions, angiographic, revascularization, in-hospital, and long-term events were recorded. We prospectively evaluated 168 patients with NA-SCAD. Average age was 52.1±9.2 years, 92.3% were women (62.3% postmenopausal). All presented with myocardial infarction. ECG showed ST-segment elevation in 26.1%, and 3.6% had ventricular tachycardia/ventricular fibrillation arrest. Fibromuscular dysplasia was diagnosed in 72.0%. Precipitating emotional or physical stress was reported in 56.5%. Majority had type 2 angiographic SCAD (67.0%), only 29.1% had type 1, and 3.9% had type 3. The majority (134/168) were initially treated conservatively. Overall, 6 of 168 patients had coronary artery bypass surgery and 33 of 168 had percutaneous coronary intervention in-hospital. Of those treated conservatively (n=134), 3 required revascularization for SCAD extension, and all 79 who had repeat angiogram ≥26 days later had spontaneous healing. Two-year major adverse cardiac events were 16.9% (retrospectively identified group) and 10.4% (prospectively identified group). Recurrent SCAD occurred in 13.1%. Conclusions—Majority of patients with NA-SCAD had fibromuscular dysplasia and type 2 angiographic SCAD. Conservative therapy was associated with spontaneous healing. NA-SCAD survivors are at risk for recurrent cardiovascular events, including recurrent SCAD.

Sex differences in clinical outcomes in patients with stable angina and no obstructive coronary artery disease

BACKGROUND We comparatively evaluated clinical outcomes in men and women presenting with stable angina with no coronary artery disease (CAD), nonobstructive CAD, and obstructive CAD on coronary angiography. METHODS We studied all patients ≥20 years with stable angina, undergoing coronary angiography in British Columbia, Canada, from July 1999 to December 2002 (n = 13,695) with maximum follow-up to 3 years. No CAD, nonobstructive CAD, and obstructive CAD were defined as 0%, 1% to 49%, and ≥50% luminal narrowing in any epicardial coronary artery, respectively. Freedom from major adverse cardiac events (MACEs), which included the combined end points of all-cause mortality, nonfatal acute myocardial infarction, nonfatal stroke, and heart failure admissions, was estimated using the Kaplan-Meier method. Hazard ratios (HRs) and 95% CIs for MACE were estimated up to 3 years postcatheterization and compared between sex and CAD groups. RESULTS Within the first year, women with nonobstructive CAD had a higher risk of MACE than men with nonobstructive CAD (adjusted HR 2.43, 95% CI 1.08-5.49). Furthermore, women with nonobstructive CAD had a 2.55-fold higher risk of MACE than women with no CAD (95% CI 1.33-4.88). In contrast, men with nonobstructive CAD had a similar risk as men with no CAD (adjusted HR 0.61, 95% CI 0.26-1.45). The differences in MACE according to extent of CAD were not evident in the longer term. CONCLUSIONS Women with stable angina and nonobstructive CAD are 3 times more likely to experience a cardiac event within the first year of cardiac catheterization than men. A prospective trial to examine the impact of medical therapy on MACE in patients with nonobstructive CAD is warranted.

Evaluation of resident attitudes and self-reported competencies in health advocacy.

BackgroundThe CanMEDS Health Advocate role, one of seven roles mandated by the Royal College of Physicians and Surgeons Canada, pertains to a physicians responsibility to use their expertise and influence to advance the wellbeing of patients, communities, and populations. We conducted our study to examine resident attitudes and self-reported competencies related to health advocacy, due to limited information in the literature on this topic.MethodsWe conducted a pilot experience with seven internal medicine residents participating in a community health promotion event. The residents provided narrative feedback after the event and the information was used to generate items for a health advocacy survey. Face validity was established by having the same residents review the survey. Content validity was established by inviting an expert physician panel to review the survey. The refined survey was then distributed to a cohort of core Internal Medicine residents electronically after attendance at an academic retreat teaching residents about advocacy through didactic sessions.ResultsThe survey was completed by 76 residents with a response rate of 68%. The majority agreed to accept an advocacy role for societal health needs beyond caring for individual patients. Most confirmed their ability to identify health determinants and reaffirmed the inherent requirements for health advocacy. While involvement in health advocacy was common during high school and undergraduate studies, 76% of residents reported no current engagement in advocacy activity, and 36% were undecided if they would engage in advocacy during their remaining time as residents, fellows or staff. The common barriers reported were insufficient time, rest and stress.ConclusionsMedical residents endorsed the role of health advocate and reported proficiency in determining the medical and bio-psychosocial determinants of individuals and communities. Few residents, however, were actively involved in health advocacy beyond an individual level during residency due to multiple barriers. Further studies should address these barriers to advocacy and identify the reasons for the discordance we found between advocacy endorsement and lack of engagement.

Sex Hormones and the QT Interval: A Review

A prolonged QT interval is a marker for an increased risk of ventricular tachyarrhythmias. Both endogenous and exogenous sex hormones have been shown to affect the QT interval. Endogenous testosterone and progesterone shorten the action potential, and estrogen lengthens the QT interval. During a single menstrual cycle, progesterone levels, but not estrogen levels, have the dominant effect on ventricular repolarization in women. Studies of menopausal hormone therapy (MHT) in the form of estrogen-alone therapy (ET) and estrogen plus progesterone therapy (EPT) have suggested a counterbalancing effect of exogenous estrogen and progesterone on the QT. Specifically, ET lengthens the QT, whereas EPT has no effect. To date, there are no studies on oral contraception (OC) and the QT interval, and future research is needed. This review outlines the current literature on sex hormones and QT interval, including the endogenous effects of estrogen, progesterone, and testosterone and the exogenous effects of estrogen and progesterone therapy in the forms of MHT and hormone contraception. Further, we review the potential mechanisms and pathophysiology of sex hormones on the QT interval.

Cardiac magnetic resonance imaging myocardial perfusion reserve index assessment in women with microvascular coronary dysfunction and reference controls

OBJECTIVE We sought to comparatively assess cardiac magnetic resonance imaging (CMRI) myocardial perfusion reserve index (MPRI) in women with confirmed microvascular coronary dysfunction (MCD) cases and reference control women. BACKGROUND Women with signs or symptoms of myocardial ischemia in the absence of obstructive coronary artery disease (CAD) frequently have MCD which carries an adverse prognosis. Diagnosis involves invasive coronary reactivity testing (CRT). Adenosine CMRI is a non-invasive test that may be useful for the detection of MCD. METHODS Fifty-three women with MCD confirmed by CRT and 12 age- and estrogen-use matched reference controls underwent adenosine CMRI. CMRI was assessed for MPRI, calculated using the ratio of myocardial blood flow at hyperemia/rest for the whole myocardium and separately for the 16 segments as defined by the American Heart Association. Statistical analysis was performed using repeated measures ANOVA models. RESULTS Compared to reference controls, MCD cases had lower MPRI values globally and in subendocardial and subepicardial regions (1.63±0.39 vs. 1.98±0.38, P=0.007, 1.51±0.35 vs. 1.84±0.34, P=0.0045, 1.68±0.38 vs. 2.04±0.41, P=0.005, respectively). A perfusion gradient across the myocardium with lower MPRI in the subendocardium compared to the subepicardium was observed for both groups. CONCLUSIONS Women with MCD have lower MPRI measured by perfusion CMRI compared to reference controls. CMRI may be a useful diagnostic modality for MCD. Prospective validation of a diagnostic threshold for MPRI in patients with MCD is needed.

Sex differences in cardiovascular disease : Impact on care and outcomes

KH Humphries, University of British Columbia M Izadnegandar, BC Centre for Improved Cardiovascular Health T Sedlak, University of British Columbia J Saw, University of British Columbia N Johnston, Uppsala University Hospital K Schenck-Gustafsson, Karolinska University Hospital and Karolinska Institutet RU Shah, University of Utah V Regitz-Zagrosek, Charité University Medicine Berlin and DZHK J Grewal, University of British Columbia Viola Vaccarino, Emory University

Spontaneous Coronary Artery Dissection Misdiagnosed as Takotsubo Cardiomyopathy: A Case Series

Spontaneous coronary artery dissection (SCAD) and Takotsubo cardiomyopathy (TTC) can both cause myocardial infarction with subsequent normalization of wall motion abnormality. Angiograms of patients with TTC at Vancouver General Hospital were reviewed for SCAD. Clinical and investigational characteristics were recorded. Nine women with nonatherosclerotic SCAD were misdiagnosed as having TTC. Their average age was 55 years. Five patients had hypertension and 4 had emotional or physical stress. Fibromuscular dysplasia was present in 4 women. Wall motion abnormalities corresponded to dissected artery location and subsequently resolved. SCAD should be included in the differential diagnosis of patients suspected of having TTC and coronary angiograms scrutinized for subtle SCAD.

Ranolazine: A Contemporary Review

Ranolazine, a piperazine derivative sold under the trade name Ranexa, is a well‐tolerated medication that selectively inhibits the late sodium current. Additionally, ranolazine has beneficial metabolic properties and does not affect heart rate or blood pressure. Ranolazine is currently approved in

Valvular aortic stenosis as a major sequelae in patients with pre-existing subaortic stenosis changing spectrum of outcomes.

OBJECTIVES The purpose of this study was to determine the prevalence of valvular aortic stenosis requiring surgery in patients with a pre-existing diagnosis of subaortic stenosis. BACKGROUND Classic teachings emphasize aortic regurgitation as the most common complication associated with discrete subaortic stenosis. We hypothesized that significant aortic stenosis may also be an important valve lesion associated with this condition. METHODS Clinical outcomes in patients with subaortic stenosis were examined. The primary outcome of interest was the prevalence of valvular aortic stenosis requiring surgery (surgical valvotomy or valve replacement). Logistic regression was used to identify variables associated with the need for surgery for aortic stenosis. RESULTS One hundred twenty-one adults with subaortic stenosis (median age 32 years) were evaluated in our clinic. Associated lesions were common: 23% had bicuspid valves and 21% had coarctation of the aorta. Seventy-nine percent of the patients had at least 1 surgical resection of subaortic tissue (median age 12 years). Moderate to severe aortic regurgitation was present in 16% of patients (19 of 121), 3 of whom required surgical intervention in adulthood. Twenty-six percent of patients (32 of 121) required surgery for valvular aortic stenosis. Valve surgery for aortic stenosis was more common in patients with concomitant bicuspid aortic valve disease (p = 0.008), coarctation of the aorta (p = 0.03), and supravalvular stenosis (p = 0.02). CONCLUSIONS Valvular aortic stenosis is a surprisingly common finding in patients with discrete subaortic stenosis. Careful clinical follow-up of this population to monitor aortic valve status continues to be warranted even after a successful surgical resection.

Sex and Ethnic Differences in Outcomes of Acute Coronary Syndrome and Stable Angina Patients With Obstructive Coronary Artery Disease

Background—The joint contribution of sex, ethnicity, and initial clinical presentation to the long-term outcomes of patients undergoing coronary angiography for acute coronary syndrome (ACS) or stable angina, in whom there is angiographic evidence for obstructive coronary artery disease, remains unknown. Methods and Results—We conducted a population-based cohort study on 49 556 adult ACS or stable angina patients with angiographic evidence of obstructive coronary artery disease (≥50% stenosis) in British Columbia. The 2-year composite outcome was all-cause death and hospital readmissions for myocardial infarction, heart failure, cerebrovascular accident, or angina after the index angiography. Sex and ethnic differences in the composite outcome were examined by clinical presentation using the Cox proportional-hazards and logistic regression models. Overall, 25.6% were women, 9.5% were South Asians, 3.0% were Chinese, and 65.9% presented with ACS. Regardless of ethnicity, women were more likely than men to have adverse outcomes, but the magnitude of the sex difference was greater in the ACS patients (Pinteraction for sex and clinical presentation=0.03). Angina readmission accounted for 45% of the composite outcome and was the main component for all groups with the exception of Chinese women with ACS. Furthermore, women were more likely than men to be readmitted for angina (odds ratio [95% confidence interval], 1.13 [1.04–1.22]). Conclusions—Higher rates of adverse events among women with obstructive coronary artery disease, regardless of ethnicity, as well as high rates of angina readmission, highlight the need for more targeted interventions to reduce the burden of angina because this presentation is clearly not benign.