Robert Faillace

Insulin Infusion in Conscious Dogs: EFFECTS ON SYSTEMIC AND CORONARY HEMODYNAMICS, REGIONAL BLOOD FLOWS, AND PLASMA CATECHOLAMINES

Cardiovascular actions of insulin were studied by intravenous infusions of insulin (4 and 8 mU/kg per min) in normal conscious dogs. This resulted in increases in cardiac output, heart rate, and left ventricular derivative of pressure with respect to time (dP/dt) and dP/dt/P, as blood glucose was reduced. The inotropic and chronotropic effects of insulin were not related to hypoglycemia, as they persisted even when blood glucose was restored to control values or when it was prevented from falling by a simultaneous infusion of glucose. These cardiac effects were accompanied by increases in plasma catecholamines, and were abolished by propranolol pretreatment. Both plasma epinephrine and norepinephrine increased during insulin hypoglycemia, but only norepinephrine increased during insulin infusion when euglycemia was maintained. Mean arterial blood pressure did not change significantly during insulin hypoglycemia, but rose if euglycemia was maintained, probably due to the selective increase in norepinephrine in the latter condition. A pressor response also occurred in propranolol-pretreated dogs during insulin hypoglycemia, but was abolished when the animals also had been pretreated with phentolamine, indicating that the vasoconstrictor action of insulin was mediated via alpha adrenergic receptors. Insulin infusion increased left ventricular work and myocardial blood flow in dogs with and without hypoglycemia. Myocardial blood flow, however, did not change significantly during insulin infusion in dogs pretreated with propranolol. As propranolol also diminished the inotropic response, it appears that the increase in myocardial blood flow caused by insulin in the normal dog is causally related to the increased myocardial metabolic demand. Insulin also produced vasomotor effects on other vascular beds. In skeletal muscle, blood flow was increased under all study conditions, except during insulin hypoglycemia after propranolol-pretreatment when unopposed alpha-mediated vasoconstriction was present. The persistent increase in flow during both alpha and beta adrenergic blockade suggests that insulin has a direct dilator effect on skeletal muscle vasculature. In the adrenal gland, flow was increased except during euglycemia, when no rise in plasma epinephrine was observed, suggesting coupling between adrenal flow and catecholamine release. In the splanchnic bed, flow was decreased during euglycemia, when plasma norepinephrine rose, and during beta adrenergic blockade with propranolol, when unopposed alpha-mediated vasoconstriction also predominated. A similar pattern was found in the kidney, except that renal blood flow also fell after combined alpha and beta adrenergic blockade. The results show that the vasomotor effects on regional flows are mediated both via adrenergic mechanisms, and in the case of skeletal muscle and kidney, via mechanisms unrelated to sympathetic stimulation.

Left atrial appendage morphology assessment for risk stratification of embolic stroke in patients with atrial fibrillation: A meta-analysis

BACKGROUND Thromboembolic event (TE) risk stratification is performed by using CHA2DS2VASc score. It has been suggested that left atrial appendage (LAA) morphology independently influences TE risk in patients with nonvalvular atrial fibrillation. LAA morphology has been classified into 4 types: chicken wing, cauliflower, windsock, and cactus. OBJECTIVE The purpose of this study was to determine TE risk for each LAA morphology in patients with atrial fibrillation with low to intermediate TE risk. METHODS A systematic review of MEDLINE, Cochrane Library, and Embase for studies that used computed tomography, tridimensional transesophageal echocardiography, and cardiac magnetic resonance imaging to categorize the LAA morphologies with assessment of TE prevalence. Odds ratio (OR) and 95% confidence intervals (CIs) were measured using the Mantel-Haenszel method. The fixed effects model was used, and if heterogeneity (I2) was >25%, effects were analyzed using a random model. RESULTS Eight studies with 2596 patients were included. Eighty-four percent (n=1872) of patients had a CHADS2 score of <2. TE risk was lower in chicken wing morphology than in non-chicken wing morphology (OR 0.46; 95% CI 0.36-0.58). Likewise, chicken wing morphology had lower TE risk than did other morphologies (chicken wing vs cauliflower: OR 0.38; 95% CI 0.26-0.56; chicken wing vs windsock: OR 0.48; 95% CI 0.31-0.73; chicken wing vs cactus: OR 0.49; 95% CI 0.36-0.66). CONCLUSION Patients with chicken wing LAA morphology are less likely to develop TE than patients with non-chicken wing morphology. LAA morphology may be a valuable criterion in predicting TE and could affect the stratification and anticoagulation management of patients with low to intermediate TE risk.

Patent foramen ovale: Unanswered questions.

The foramen ovale is a remnant of the fetal circulation that remains patent in 20-25% of the adult population. Although long overlooked as a potential pathway that could produce pathologic conditions, the presence of a patent foramen ovale (PFO) has been associated with a higher than expected frequency in a variety of clinical syndromes including cryptogenic stroke, migraines, sleep apnea, platypnea-orthodeoxia, deep sea diving associated decompression illness, and high altitude pulmonary edema. A unifying hypothesis is that a chemical or particulate matter from the venous circulation crosses the PFO conduit between the right and left atria to produce a variety of clinical syndromes. Although observational studies suggest a therapeutic benefit of PFO closure compared to medical therapy alone in patients with cryptogenic stroke, 3 randomized controlled trials (RCTs) did not confirm the superiority of PFO closure for the secondary prevention of stroke. However, meta-analyses of these RCTs demonstrate a significant benefit of PFO closure over medical therapy alone. Similarly, observational studies provide support for PFO closure for symptomatic relief of migraines. But one controversial randomized study failed to replicate the results of the observational studies while another two demonstrated a partial benefit. The goal of this review is to discuss the clinical conditions associated with PFO and provide internists and primary care physicians with current data on PFO trials, and clinical insight to help guide their patients who are found to have a PFO on echocardiographic testing.

The role of the out-of-operating room anesthesiologist in the care of the cardiac patient.

Modern invasive cardiovascular procedures require patients to be both comfortable and cooperative. In addition, these procedures demand the complete attention of the attending cardiovascular specialist, and, to a large degree, the outcomes of these procedures depend on the amount of focus and concentration the cardiovascular specialist can give to performing the procedure itself. A team approach using the specialized skills of a cardiologist and an anesthesiologist frequently is required to optimize results. This article clearly delineates the procedures cardiologists perform that might involve anesthesiologists. Mutual knowledge, understanding, and respect are fundamental requirements for integration of cardiology and anesthesia services to optimize patient outcomes.

Atrial Fibrillation Identified During Echocardiography in a Patient with Recurrent Cardioembolic Events: A Case Report.

Patient: Female, 80 Final Diagnosis: Stroke Symptoms: Weakness • left sided Medication: — Clinical Procedure: Echocardiogram Specialty: Naurology Objective: Unusual clinical course Background: Stroke is the major cause of disability and the fifth leading cause of death in the United States. In 30–40% of strokes the etiology remains uncertain or unknown. Identifying the cause of a cerebrovascular event offers the opportunity for an intervention that may decrease the risk of future stroke and thus prevent the resultant impairment. Case Report: We report the case of an 80-year-old African American woman with a prior right middle cerebral artery stroke, who presented to the hospital with new left-sided weakness and was found to have a new right-sided frontal lobe infarct. Twenty-four hour Holter monitoring performed during this hospitalization and prior 24-h electrocardiogram (ECG) recording did not reveal an arrhythmia. However, the patient was found to have an isolated episode of atrial fibrillation (AF) during an echocardiogram as part of the evaluation for stroke etiology. Conclusions: AF is an important and treatable cause of recurrent stroke and needs to be ruled out by thorough evaluation before the diagnosis of cryptogenic stroke is assigned. Despite meticulous diagnostic work-up, many strokes caused by paroxysmal AF remain undetected and longer ECG monitoring (>24 h) may be required.

Assessment of Implantable Cardioverter-Defibrillator Used in Heart Failure with Reduced Ejection Fraction as Primary Prevention in an Underserved Population

Implantable cardioverter-defibrillator (ICD) implantation has been one of the milestones in the treatment of heart failure providing a significant survival benefit. Current guidelines recommend that patients who have a sustained low left ventricular ejection fraction (LVEF) of 35% or less should be evaluated for ICD for primary prophylaxis (P-ICD). Our study aimed to investigate the use of P-ICD and associated outcomes in Jacobi Medical Center, a municipal New York City public teaching hospital serving an inner-city patient population located in Bronx, NY.

The predictive value of baseline pulmonary hypertension in early and long term cardiac and all-cause mortality after transcatheter aortic valve implantation for patients with severe aortic valve stenosis: A systematic review and meta-analysis

BACKGROUND Transcatheter aortic valve implantation (TAVI) is a safe and effective alternative to surgical aortic valve replacement (SAVR) for the treatment of severe aortic valve stenosis (AS). The impact of concomitant baseline elevated pulmonary artery pressures on outcomes after TAVI has not been established, since different studies used different definitions of pulmonary hypertension (PH). OBJECTIVE To determine the association of PH with early and late cardiac and all-cause mortality after TAVI. METHODS We performed a meta-analysis of studies comparing patients with elevated pulmonary artery pressures (defined as pulmonary hypertension or not) versus patients without elevated pulmonary artery pressures undergoing TAVI. We first performed stratified analyses based on the different PH cut-off values utilized by the included studies and subsequently pooled the studies irrespective of their cut-off values. We used a random effects model for the meta-analysis and assessed heterogeneity with I-square. Separate meta-analyses were performed for studies reporting outcomes as hazards ratios (HRs) and relative risks (RRs). Subgroup analyses were performed for studies published before and after 2013. Meta-regression analysis in order to assess the effect of chronic obstructive pulmonary disease and mitral regurgitation were performed. RESULTS In total 22 studies were included in this systematic review. Among studies presenting results as HR, PH was associated with increased late cardiac mortality (HR: 1.8. 95% CI: 1.3-2.3) and late all-cause mortality (HR: 1.56; 95% CI: 1.1-2). The PH cut-off value that was most likely to be associated with worst outcomes among the different endpoints was pulmonary artery systolic pressure of 60 mm Hg (HR: 1.8; 95% CI: 1.3-2.3; I2 = 0, for late cardiac mortality and HR: 1.52; 95% CI: 1-2.1; I2 = 85% for late all-cause mortality). CONCLUSION This systematic review and meta-analysis emphasizes the importance of baseline PH in predicting mortality outcomes after TAVI. Additional studies are needed to clarify the association between elevated baseline pulmonary artery pressures and outcomes after TAVI.

Percutaneous closure of patent foramen ovale vs. medical treatment for patients with history of cryptogenic stroke: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND Patients with history of cryptogenic stroke are more likely to have a patent foramen ovale (PFO) and should be managed with antithrombotic agents, while the alternative option is percutaneous closure of PFOs. Our aim was to perform a meta-analysis of randomized controlled trials (RCTs) comparing percutaneous closure vs. medical treatment for patients with PFO and prior cryptogenic stroke. METHODS Medline, Scopus and Cochrane databases were reviewed. A random-effect model meta-analysis was used and I-square was utilized to assess the heterogeneity. New ischemic stroke was defined as the primary endpoint. A sensitivity analysis was performed for Amplatzer device. Subgroup analyses were performed for different patient and PFO characteristics for the composite endpoints as defined by the included RCTs. RESULTS In total of 3440 patients were included in this meta-analysis. Closure devices were superior to medical therapy for prevention of recurrent ischemic strokes (HR = 0.29; CI: 0.02-0.56), but were associated with increased risk of new onset of atrial fibrillation (AF) and atrial flutter (RR = 4.67; CI: 2.22-9.81). However, in the sensitivity analysis for Amplatzer device, there was no difference between the two groups in new onset of atrial arrhythmias. Closure devices were superior across all different subgroups when compared to medical treatment with the exception of patients with a small shunt. CONCLUSION This meta-analysis shows that closure devices for patients with PFO and history of cryptogenic stroke can significantly decrease the risk of a new ischemic stroke. The use of Amplatzer device was not associated with increased risk of newly diagnosed atrial arrhythmias.

Is 30-Day Mortality after Admission for Heart Failure an Appropriate Metric for Quality?

BACKGROUND The Centers for Medicare and Medicaid Services (CMS) model for publicly reporting national 30-day-risk-adjusted mortality rates for patients admitted with heart failure fails to include clinical variables known to impact total mortality or take into consideration the culture of end-of-life care. We sought to determine if those variables were related to the 30-day mortality of heart failure patients at Geisinger Medical Center. METHODS Electronic records were searched for patients with a diagnosis of heart failure who died from any cause during hospitalization or within 30 days of admission. RESULTS There were 646 heart-failure-related admissions among 530 patients (1.2 admissions/patient). Sixty-seven of the 530 (13%) patients died: 35 (52%) died during their hospitalization and 32 (48%) died after discharge but within 30 days of admission; of these, 27 (40%) had been transferred in for higher-acuity care. Fifty-one (76%) died from heart failure, and 16 (24%) from other causes. Fifty-five (82%) patients were classified as American Heart Association Stage D, 58 (87%) as New York Heart Association Class IV, and 30 (45%) had right-ventricular systolic dysfunction. None of the 32 patients who died after discharge met recommendations for beta-blockers. Criteria for prescribing angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and mineralocorticoid receptor blockers were not met by 33 of the 34 patients (97%) with heart failure with reduced ejection fraction not on one of those drugs. Fifty-seven patients (85%) had a do-not-resuscitate (DNR) status. CONCLUSION A majority of heart failure-related mortality was among patients who opted for a DNR status with end-stage heart failure, limiting the appropriateness of administering evidence-based therapies. No care gaps were identified that contributed to mortality at our institution. The CMS 30-day model fails to take important variables into consideration.

Transient Giant R Wave as a Marker for Ischemia in Unstable Angina

Unstable angina is a clinical diagnosis that may present with or without electrocardiographic changes. The “giant R wave” on electrocardiogram has been reported as a manifestation of acute ischemia; however, it is a rare finding in current clinical practice. We describe a case of a patient with unstable angina and a transient “giant R wave” pattern with a culprit lesion in the right coronary artery.