Claire S. Duvernoy

HRS expert consensus statement on the diagnosis and management of arrhythmias associated with cardiac sarcoidosis.

David H. Birnie, MD (Chair), William H. Sauer, MD, FHRS, CCDS (Chair), Frank Bogun, MD, Joshua M. Cooper, MD, FHRS, Daniel A. Culver, DO,* Claire S. Duvernoy, MD, Marc A. Judson, MD, Jordana Kron, MD, Davendra Mehta, MD, PhD, FHRS, Jens Cosedis Nielsen, MD, Amit R. Patel, MD, Tohru Ohe, MD, FHRS, Pekka Raatikainen, MD, Kyoko Soejima, MD From the University of Ottawa Heart Institute, Ottawa, Ontario, Canada, University of Colorado, Aurora, Colorado, University of Michigan, Ann Arbor, Michigan, Temple University Health System, Philadelphia, Pennsylvania, Cleveland Clinic, Cleveland, Ohio, VA Ann Arbor Healthcare System and University of Michigan, Ann Arbor, Michigan, Albany Medical College, Albany, New York, Virginia Commonwealth University, Richmond, Virginia, Mount Sinai School of Medicine, New York, New York, Aarhus University Hospital, Aarhus, Denmark, University of Chicago, Chicago, Illinois, Sakakibara Heart Institute of Okayama, Okayama, Japan, Heart Center, Tampere University Hospital, Tampere, Finland, and Kyorin University School of Medicine, Mitaka City, Japan.

Evaluation of Patients With Severe Symptomatic Aortic Stenosis Who Do Not Undergo Aortic Valve Replacement: The Potential Role of Subjectively Overestimated Operative Risk

Background—Some patients with severe symptomatic aortic stenosis (AS) do not undergo aortic valve replacement (AVR) despite demonstrated symptomatic and survival advantages and despite unequivocal guideline recommendations for surgical evaluation. Methods and Results—In 3 large tertiary care institutions (university, Veterans Affairs, and private practice) in Washtenaw County, Mich, patients were identified with unrefuted echocardiography/Doppler evidence of severe AS during calendar year 2005. Medical records were retrospectively reviewed for symptoms, referral for AVR, calculated operative risk for AVR, and rationale as to why patients did not undergo valve replacement. Of 369 patients with severe AS, 191 (52%) did not undergo AVR. Of these, 126 (66%, 34% of total) had symptoms consistent with AS. The most common reasons cited for absent intervention were comorbidities with high operative risk (61 patients [48%]), patent refusal (24 patients [19%]), and symptoms unrelated to AS (24 patients [19%]). Operated patients had a lower Society of Thoracic Surgery-calculated perioperative mortality risk than unoperated patients (1.8% [interquartile range, 1.0 to 3.0%] versus 2.7% [interquartile range, 1.6 to 5.5%], P<0.001). However, 28 (24%) of 126 unoperated symptomatic patients had a calculated perioperative risk less than the median risk for patients who underwent AVR. Only 57 (30%) of 191 unoperated patients were evaluated by a cardiac surgeon. There were similar rates of intervention across practice settings, and similar rates of unoperated patients despite symptoms and low operative risk. Conclusions—One third of patients with severe AS are symptomatic but do not undergo AVR, with similar findings in multiple practice environments. For most unoperated patients, objectively calculated operative risks did not appear prohibitive. Despite this, a minority of unoperated patients were referred for surgical consultation. Some patients with severe symptomatic AS may be inappropriately denied access to potentially life-saving therapy.

Assessment of diagnostic performance of quantitative flow measurements in normal subjects and patients with angiographically documented coronary artery disease by means of nitrogen-13 ammonia and positron emission tomography

OBJECTIVES Regional myocardial blood flow (MBF) and flow reserve measurements using nitrogen-13 (N-13) ammonia positron emission tomography (PET) were compared with quantitative coronary angiography to determine their utility in the detection of significant coronary artery disease (CAD). BACKGROUND Dynamic PET protocols using N-13 ammonia allow regional quantification of MBF and flow reserve. To establish the diagnostic performance of this method, the sensitivity and specificity must be known for varying decision thresholds. METHODS MBF and flow reserve for three coronary territories were determined in 20 normal subjects and 31 patients with angiographically documented CAD by means of dynamic PET and a three-compartment model for N-13 ammonia kinetics. Ten normal subjects defined the normal mean and SD of MBF and flow reserve, and 10 normal subjects were compared with patients. PET flow obtained in the territory with the most severe stenosis in each patient was correlated with the angiographic assessment of the stenosis (severity > or = 50%, > or = 70%, > or = 90%). Receiver operating characteristic (ROC) curve analysis was performed for 1.5, 2.0, 2.5, 3.0 and 4.0 SD of flow abnormalities. RESULTS MBF and flow reserve values from the normal subjects and from territories with documented stenoses > or = 50% were significantly different (p < 0.05). A significant difference was found between normal subjects and angiographically normal territories of patients with CAD. High diagnostic accuracy and sensitivity, with moderately high specificity, were demonstrated for detection of all stenoses. CONCLUSIONS Quantification of myocardial perfusion using dynamic PET and N-13 ammonia provides a high performance level for the detection and localization of CAD. The specificity of dynamic PET was excellent in patients with a low likelihood of CAD, whereas an abnormal flow reserve in angiographically normal territories was postulated to represent early functional abnormalities of vascular reactivity.

Current role of sodium bicarbonate-based preprocedural hydration for the prevention of contrast-induced acute kidney injury: a meta-analysis.

BACKGROUND The optimal hydration strategy for prevention of contrast-induced acute kidney injury (AKI) remains unknown. The purpose of this meta-analysis is to compare the effectiveness of normal saline (NS) versus sodium bicarbonate hydration (NaHCO(3)) for prevention of contrast-induced AKI. METHODS We performed a meta-analysis of randomized controlled trials that compared saline-based hydration with sodium bicarbonate-based hydration regimen for prophylaxis of contrast-induced AKI. The literature search included MEDLINE, EMBASE, and Cochrane databases (2000 to October 2007); conference proceedings; and bibliographies of retrieved articles. Information was extracted on study design, sample characteristics, and interventions. Random-effects models were used to calculate summary risk ratios for contrast-induced AKI, need for hemodialysis, and death. RESULTS Seven trials with 1,307 subjects were included. Preprocedural hydration with sodium bicarbonate was associated with a significant decrease in the rate of contrast-induced AKI (5.96% in the NaHCO(3) arm versus 17.23% in the NS arm, summary risk ratio 0.37, 95% CI 0.18-0.714, P = .005). There was no difference in the rates of postprocedure hemodialysis or death. Formal testing revealed moderate heterogeneity and a strong likelihood of publication bias. CONCLUSIONS Although sodium bicarbonate hydration was found to be superior to NS in prevention of contrast-induced AKI, these results are in the context of study heterogeneity and, likely, publication bias. An adequately powered randomized controlled trial is warranted to define the optimal hydration strategy in patients at high risk of contrast-induced AKI who are scheduled to undergo contrast administration.

Emergence of Nonobstructive Coronary Artery Disease: A Woman's Problem and Need for Change in Definition on Angiography.

Recognition of ischemic heart disease (IHD) is often delayed or deferred in women. Thus, many at risk for adverse outcomes are not provided specific diagnostic, preventive, and/or treatment strategies. This lack of recognition is related to sex-specific IHD pathophysiology that differs from traditional models using data from men with flow-limiting coronary artery disease (CAD) obstructions. Symptomatic women are less likely to have obstructive CAD than men with similar symptoms, and tend to have coronary microvascular dysfunction, plaque erosion, and thrombus formation. Emerging data document that more extensive, nonobstructive CAD involvement, hypertension, and diabetes are associated with major adverse events similar to those with obstructive CAD. A central emerging paradigm is the concept of nonobstructive CAD as a cause of IHD and related adverse outcomes among women. This position paper summarizes currently available knowledge and gaps in that knowledge, and recommends management options that could be useful until additional evidence emerges.

Gender differences in adverse outcomes after contemporary percutaneous coronary intervention: An analysis from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) percutaneous coronary intervention registry

BACKGROUND Prior studies have shown a relationship between female gender and adverse outcomes after percutaneous coronary interventions (PCIs). Whether this relationship still exists with contemporary PCI remains to be determined. METHODS We evaluated gender differences in clinical outcomes in a large registry of contemporary PCI. Data were prospectively collected from 22,725 consecutive PCIs in a multicenter regional consortium (Blue Cross Blue Shield of Michigan Cardiovascular Consortium) between January 2002 and December 2003. The primary end point was in-hospital all-cause mortality; other clinical outcomes evaluated included in-hospital death, vascular complications, transfusion, postprocedure myocardial infarction, stroke, and a combined major cardiovascular adverse event (MACE) end point including myocardial infarction, death, stroke, emergency coronary artery bypass grafting, and repeated PCI at the same site. Independent predictors of adverse outcomes were identified using multivariate logistic regression analysis. RESULTS Compared with men, women were older, had a higher prevalence of comorbidities, and had a significantly higher frequency of adverse outcomes after PCI. After adjustment for baseline demographics, comorbidities, clinical presentation, and lesion characteristics, female gender was associated with an increased risk of in-hospital death, vascular complication, blood transfusion, stroke, and MACE. The relationship between female gender and increased risk of death and MACE was no longer present after further adjustment for kidney function and low body surface area. CONCLUSIONS Differences in mortality rates between men and women no longer exist after PCI. However, our data suggest that technological advancements have not completely offset the relationship between gender and adverse outcomes after PCI.

Gender differences in myocardial blood flow dynamics: Lipid profile and hemodynamic effects

OBJECTIVES The purpose of the study was to compare myocardial blood flow (MBF) in hyperlipidemic postmenopausal women and age-matched hyperlipidemic men, and to analyze the relationship between cholesterol subfractions and myocardial blood flow in men and women. BACKGROUND Women are protected from coronary artery disease (CAD) events until well after menopause, in part due to gender-specific differences in lipid profiles. METHODS To examine the effect of these influences on coronary microcirculation, MBF was quantitated with N-13 ammonia/PET (positron emission tomography) at rest and during adenosine hyperemia in 15 women and 15 men, all nondiabetic, who were matched for age and total cholesterol levels (53+/-4 vs. 50+/-8 years, p = NS, 6.44+/-1.1 vs. 6.31+/-0.85 mmol/liter, or 249+/-41 vs. 244+/-33 mg/dl, p = NS). RESULTS Women had significantly higher high density lipoprotein (HDL) and lower triglyceride (Tg) levels than did men, and they showed significantly higher resting MBF and stress MBF levels. Significant correlations were found between resting and hyperemic MBF and HDL and Tg levels (r = 0.44, p < 0.02 for stress MBF vs. HDL; r = 0.48, p < 0.007 for stress MBF vs. Tg). Gender was the strongest predictor of hyperemic MBF in multivariate analysis. Women responded to adenosine hyperemia with a significantly higher heart rate than did men, and hemodynamic factors correlated significantly with blood flow both at rest and during stress. CONCLUSIONS These data suggest that the favorable lipid profile seen in women may be associated with preserved maximal blood flow in the myocardium.

Myocardial blood flow and coronary flow reserve late after anatomical correction of transposition of the great arteries

OBJECTIVES Myocardial blood flow (MBF) in children late after arterial switch operation (ASO) was investigated quantitatively by positron emission tomography (PET). BACKGROUND In children with transposition of the great arteries (TGA), ASO is widely accepted as the management of choice. The long-term patency of coronary arteries after surgical transfer to the neo-aorta, however, remains a concern. METHODS Twenty-two normally developed, symptom-free children were investigated by PET with nitrogen-13 ammonia at rest and during adenosine vasodilation 10+/-1 years after ASO. A subgroup of 15 children (9+/-1 years; group A) had simple TGA and underwent ASO within 20 days after birth while 7 (13+/-3 years; group B) had complex TGA and underwent ASO and correction of associated anomalies later after birth. Ten young, healthy adults (26+/-6 years) served as the control group. RESULTS Resting MBF was not different between groups. After correction for the rate-pressure product as an index of cardiac work, younger children of group A had significantly higher MBF at rest compared to healthy adults (102+/-29 vs. 77+/-6 ml/100 g/min; p = 0.012) while flow in group B was not different from the other groups (85+/-22 ml/100 g/min; p = NS). Hyperemic blood flows were significantly lower in both groups after ASO compared to normals (290+/-42 ml/100 g/min for group A, 240+/-28 for group B, 340+/-57 for normals; p < 0.01); thus, coronary flow reserve was significantly lower in both groups after ASO compared to healthy adults (3.0+/-0.6 for group A, 2.9+/-0.6 for group B, 4.6+/-0.9 for normals; p < 0.01). CONCLUSIONS Blood flow measurements suggest decreased coronary reserve in the absence of ischemic symptoms in children late after arterial switch repair of TGA. The global impairment of stress flow dynamics may indicate altered vasoreactivity; however, the prognostic significance of these findings needs to be determined.

Management of Cardiogenic Shock Attributable to Acute Myocardial Infarction in the Reperfusion Era

Cardiogenic shock is the leading cause of death among patients hospitalized with acute myocardial infarction. It is defined as tissue hypoperfusion resulting from ventricular pump failure in the presence of adequate intravascular volume. Rapid assessment and triage of patients presenting in cardiogenic shock followed by appropriate institution of supportive therapies including vasopressor and inotropic agents, mechanical ventilatory support, and intra-aortic balloon pump counterpulsation are critical for effective management of these patients. However, emergency percutaneous coronary intervention or coronary artery bypass graft surgery is required to decrease mortality rates. Novel approaches, including inhibition of nitric oxide synthase and new mechanical support devices, may further decrease mortality rates, which remain high despite reperfusion therapy.

Raloxifene use in clinical practice: efficacy and safety.

Objective and Methods: In this article, we provide an interdisciplinary concise review of the effects of raloxifene on breast, bone, and reproductive organs, as well as the adverse events that may be associated with its use. Results: Raloxifene has been shown to prevent osteoporosis in postmenopausal women (PMW) with low bone mass and prevent vertebral fractures in those with osteoporosis/low bone mass; it has not been shown to reduce the risk of nonvertebral fractures. Raloxifene reduces the risk of invasive breast cancer in PMW with osteoporosis or at high risk of breast cancer. The risk of venous thromboembolism has been consistently shown to be increased with raloxifene, so it should not be used in women at high risk of venous thromboembolism. Although raloxifene does not increase, nor decrease, the risk of coronary or stroke events overall, in the raloxifene trial of PMW at increased risk of coronary events, the incidence of fatal stroke was higher in women assigned raloxifene versus placebo. Conclusions: Based on its approved indications, it is appropriate to prescribe raloxifene to prevent or treat osteoporosis, as well as to reduce the risk of invasive breast cancer in PMW with osteoporosis or at high risk of breast cancer. Women at increased risk of both fracture and invasive breast cancer are those most likely to receive a dual benefit with raloxifene. Decision making must involve the incorporation of the womans personal feelings about the risks and benefits of raloxifene therapy, balanced with her interest in reducing risk of fractures and breast cancer through pharmacological intervention.