Management of a patient presenting with anterior STEMI with concomitant COVID-19 infection early in the course of the U.S. pandemic.

The coronavirus disease-2019 (COVID-19) is a viral illness with heterogenous clinical manifestations, ranging from mild symptoms to severe acute respiratory distress syndrome and shock caused by the severe acute respiratory syndrome coronavirus-2. The global healthcare community is rapidly learning more about the effects of COVID-19 on the cardiovascular system, as well as the strategies for management of infected patients with cardiovascular disease. There is minimal literature available surrounding the relationship between COVID-19 infection and acute coronary syndrome. We describe the case of a woman who presented with an acute anterior ST-elevation myocardial infarction managed by primary percutaneous coronary intervention, who subsequently developed severe COVID-19 infection and ultimately succumbed to multisystem organ failure.

Dofetilide-Associated QT Prolongation: Total Body Weight Versus Adjusted or Ideal Body Weight for Dosing.

Dofetilide is an antiarrhythmic drug with dosing based on the Cockcroft-Gault formula using total body weight (TBW). We investigated the impact of calculating dofetilide dose using adjusted body weight (ABW) or ideal body weight (IBW) on subsequent dose reduction or discontinuation. We conducted a retrospective review of 265 patients admitted to an academic medical center for initiation of dofetilide using TBW. Dosing was recalculated using ABW or IBW. Patients who would have received a reduced dose using ABW or IBW (reduced dose group) were compared with patients whose dose would not have changed (same dose group). Manual measurement of QT intervals was performed. We found that Forty-one of 265 patients (15%) would have received a lower initial dose of dofetilide based on ABW. Patients in this reduced dose group had 2.95 times greater odds of drug discontinuations or dose reductions due to QTc prolongation (95% confidence interval, 1.47-5.90; P < 0.01) compared with the same dose group. Seventy-seven of 265 patients (29%) would have received a lower initial dose of dofetilide based on IBW. Patients in this reduced dose group had 1.78 times greater odds of drug discontinuations or dose reductions due to QTc prolongation (95% confidence interval, 0.98-3.21; P = 0.056) compared with the same dose group. These data suggest that caution should be used when dosing dofetilide using TBW, as it may lead to a greater frequency of dose reduction or discontinuation compared with dosing using ABW or IBW.

Constrictive pericarditis: old disease, new approaches.

Constrictive pericarditis is a disorder of cardiac filling caused by an inelastic pericardium. This treatable cause of heart failure should be considered in all patients with unexplained right heart failure symptoms or signs, especially when the left ventricular ejection fraction is preserved. Diagnosing constrictive pericarditis remains challenging, and the most effective tools are designed to identify its unique pathophysiologic mechanisms: dissociation of intrathoracic and intracardiac pressures and enhanced ventricular interaction. The cornerstone of the diagnostic work-up remains comprehensive echocardiography with Doppler, but cross-sectional imaging and invasive hemodynamic assessment may be necessary in some cases. Cardiac MRI is particularly helpful in identifying those patients who may have inflammatory constriction that would resolve with anti-inflammatory therapy. Complete surgical pericardiectomy remains the only definitive treatment for patients with chronic constriction.

The effect of St John's Wort on the pharmacodynamic response of clopidogrel in hyporesponsive volunteers and patients: increased platelet inhibition by enhancement of CYP3A4 metabolic activity.

Clopidogrel is metabolically activated by cytochrome P450 (CYP) isoenzymes. We evaluated whether St. John's wort (SJW), a CYP2C19 and CYP3A4 inducer, enhances the pharmacodynamic response of clopidogrel. Volunteers (n = 45) were screened for clopidogrel hyporesponsiveness after a 300-mg load. After a 7-day washout, hyporesponders (n = 10) received 14 days of SJW (300 mg 3 times a day) followed by a second 300-mg clopidogrel. Platelet aggregation was measured at 0, 2, 4, and 6 hours postloading; hepatic CYP3A4 activity was simultaneously determined at 0 and 4 hours by the erythromycin breath test. A prospective, randomized, double-blind pilot study was conducted in postcoronary stent patients (n = 85) on clopidogrel 75 mg/d screened for clopidogrel hyporesponsiveness. Hyporesponders (n = 20) were randomized to SJW (n = 10) or placebo (n = 10); platelet aggregation was measured before and after 14 days of therapy. In volunteers, SJW decreased platelet aggregation (59% ± 14% vs. 40% ± 15% at 2 hours, P = 0.02; 56% ± 10% vs. 44% ± 13% at 4 hours, P < 0.03; and 55% ± 14% vs. 37% ± 14% at 6 hours, P = 0.01) and increased CYP3A4 activity (2.1% ± 0.4% CO2 exhaled per hour before vs. 2.9% ± 0.6% CO2 exhaled per hour after SJW, P = 0.002). In patients, SJW decreased platelet reactivity (226 ± 39 vs. 185 ± 49 P2Y12 reactivity units, P = 0.0002) and increased platelet inhibition (23% ± 11% vs. 41% ± 16%, P = 0.002). SJW may be a future therapeutic option to increase CYP metabolic activity and antiplatelet effect of clopidogrel in hyporesponders.

Modern Management of ST-Segment Elevation Myocardial Infarction.

Disruption of intracoronary plaque with thrombus formation resulting in severe or total occlusion of the culprit coronary artery provides the pathophysiologic foundation for ST-segment elevation myocardial infarction (STEMI). Management of STEMI focuses on timely restoration of coronary blood flow along with antithrombotic therapies and secondary prevention strategies. The purpose of this review is to discuss the epidemiology, pathophysiology, and diagnosis of STEMI. In addition, the review will focus on guideline-directed therapy for these patients and review potential associated complications.

Perioperative peripheral nerve injuries: a retrospective study of 380,680 cases during a 10-year period at a single institution.

BACKGROUND: Peripheral nerve injuries represent a notable source of anesthetic complications and can be debilitating. The objective of this study was to identify associations with peripheral nerve injury in a broad surgical population cared for in the last decade. METHODS: At a tertiary care university hospital, the quality assurance, closed claims, and institution-wide billing code databases were searched for peripheral nerve injuries over a 10-yr period. Each reported case was individually reviewed to determine whether a perioperative injury occurred, defined as a new sensory and/or motor deficit. The location and type of the injury were also identified. Nerve complications as a result of the surgical procedure itself were excluded, and an expert review panel assisted in the adjudication of unclear cases. Patient preoperative characteristics, anesthetic modality, and surgical specialty were evaluated for associations. RESULTS: Of all patients undergoing 380,680 anesthetics during a 10-yr period, 185 patients were initially identified as having nerve injuries, and after review, 112 met our definition of a perioperative nerve injury (frequency = 0.03%). Hypertension, tobacco use, and diabetes mellitus were significantly associated with perioperative peripheral nerve injuries. General and epidural anesthesia were associated with nerve injuries. Significant associations were also found with the following surgical specialties: Neurosurgery, cardiac surgery, general surgery, and orthopedic surgery. CONCLUSIONS: To our knowledge, this is the largest number of consecutive patients ever reviewed for all types of perioperative peripheral nerve injuries. More importantly, this is the first study to identify associations of nerve injuries with hypertension, anesthetic modality, and surgical specialty.

Cardiac Rehabilitation in a Rural Setting: OPTIMIZATION OF REFERRAL AND PARTICIPATION RATES.

PURPOSE: The cardiac rehabilitation (CR) program at Dartmouth-Hitchcock Medical Center (DHMC) devotes a nurse to the inpatient units in an attempt to optimize the referral process. This report defines the rates of referral and participation at DHMC and explores potential factors that affect participation. METHODS: Seven hundred ten consecutive patients who underwent percutaneous coronary intervention, coronary artery bypass grafting, or valve surgery from January 1, 2015 to June 30, 2015 were reviewed to determine whether the patient was referred for CR. Participation rates and the effect of time delay and patient-specific factors on participation were examined. RESULTS: Six hundred ninety-eight (98%) of the 710 post-procedural patients were evaluated by the inpatient rehabilitation nurse. One hundred sixty-seven patients were ineligible for outpatient therapy on the basis of established criteria; the remaining 543 patients were referred to DHMC or regional rehabilitation programs. Of those referred to the on-site program at DHMC, 84% participated. Of those referred to regional programs, 60% participated. There was an inverse correlation (r = -0.82; P = .003) between wait times and participation rates for the various programs. CONCLUSIONS: Despite its rural location with a large geographic catchment area, DHMC achieves high rates of CR referral and participation. The approach used at DHMC, which includes a CR nurse working with the inpatient cardiac services, a strong level of integration with the physician community, and well-developed relationships with regional rehabilitation programs, may be helpful for those programs wishing to improve referral and participation rates. Shorter wait times between hospital discharge and initiation of rehabilitation may improve participation rates.

Constrictive pericarditis: diagnosis, management and clinical outcomes.

Constrictive pericarditis (CP) is a form of diastolic heart failure that arises because an inelastic pericardium inhibits cardiac filling. This disorder must be considered in the differential diagnosis for unexplained heart failure, particularly when the left ventricular ejection fraction is preserved. Risk factors for the development of CP include prior cardiac surgery and radiation therapy, but most cases are still deemed to be idiopathic. Making the diagnosis may be challenging and requires meticulous echocardiographic assessment, often supplemented by cross-sectional cardiac imaging and haemodynamic catheterisation. The key pathophysiological concepts, which serve as the basis for many of the diagnostic criteria, remain: (1) dissociation of intrathoracic and intracardiac pressures and (2) enhanced ventricular interaction. Complete surgical pericardiectomy is the only effective treatment for chronic CP. A subset of patients with subacute inflammatory CP, often identified by cardiac MRI, may respond to anti-inflammatory treatments.

Spontaneous Closure of a Secundum Atrial Septal Defect.

Spontaneous closure of an atrial septal defect (ASD) is well described in pediatric cardiology but may be less familiar to adult internists and cardiologists. We report a moderately sized 6-mm ASD that closed spontaneously without intervention. A literature review found that a smaller defect size and an early age of diagnosis are the most important predictors of closure. Possible mechanisms of a spontaneous ASD closure include adaptive endothelial migration, limited myocardial proliferation, and fibroblast migration with extracellular matrix deposition.

Constrictive Pericarditis.

Constrictive pericarditis is a potentially treatable cause of diastolic heart failure that arises because a diseased, inelastic pericardium restricts ventricular diastolic expansion. Affected patients present with heart failure with predominant right-sided symptoms and signs. The key to diagnosis is identification of the unique hemodynamic properties associated with constriction: dissociation of intrathoracic and intracardiac pressures and enhanced ventricular interaction. Comprehensive echocardiography with Doppler imaging is useful, but invasive hemodynamic assessment and cross-sectional imaging may be required for confirmation. Cardiac MRI provides an opportunity to evaluate for pericardial inflammation. Most cases of chronic constriction are progressive and life limiting, and require surgical pericardiectomy.

Brugada Syndrome Presenting as Polymorphic Ventricular Tachycardia-Ventricular Fibrillation Lasting 94 Seconds Recorded on an Ambulatory Monitor.

IMPORTANCE: Cardiac arrhythmias are common causes of syncope. Brugada syndrome is an uncommon but serious genetic arrhythmia disorder that can be unmasked by medicines causing sodium channel blockade. OBSERVATIONS: This report documents a case of Brugada syndrome and polymorphic ventricular tachycardia-ventricular fibrillation not initially recognized in a patient taking nortriptyline and experiencing syncope. It also illustrates one of the longest episodes of ventricular fibrillation recorded on an ambulatory monitor (94 seconds). Although the baseline electrocardiogram did not demonstrate a typical appearance for Brugada syndrome, provocative testing with flecainide in this patient with documented polymorphic ventricular tachycardia revealed a Brugada electrocardiogram pattern. CONCLUSIONS AND RELEVANCE: Vigilance should be maintained for arrhythmia substrates such as Brugada syndrome in patients with typical symptoms when they are prescribed membrane-active medicines. Long-term ambulatory rhythm monitors can provide useful information in these cases, especially when symptoms are infrequent.

Echocardiographic diagnosis of constrictive pericarditis: Mayo Clinic criteria.

BACKGROUND: Constrictive pericarditis is a potentially reversible cause of heart failure that may be difficult to differentiate from restrictive myocardial disease and severe tricuspid regurgitation. Echocardiography provides an important opportunity to evaluate for constrictive pericarditis, and definite diagnostic criteria are needed. METHODS AND RESULTS: Patients with surgically confirmed constrictive pericarditis (n=130) at Mayo Clinic (2008-2010) were compared with patients (n=36) diagnosed with restrictive myocardial disease or severe tricuspid regurgitation after constrictive pericarditis was considered but ruled out. Comprehensive echocardiograms were reviewed in blinded fashion. Five principal echocardiographic variables were selected based on prior studies and potential for clinical use: (1) respiration-related ventricular septal shift, (2) variation in mitral inflow E velocity, (3) medial mitral annular e' velocity, (4) ratio of medial mitral annular e' to lateral e', and (5) hepatic vein expiratory diastolic reversal ratio. All 5 principal variables differed significantly between the groups. In patients with atrial fibrillation or flutter (n=29), all but mitral inflow velocity remained significantly different. Three variables were independently associated with constrictive pericarditis: (1) ventricular septal shift, (2) medial mitral e', and (3) hepatic vein expiratory diastolic reversal ratio. The presence of ventricular septal shift in combination with either medial e'≥9 cm/s or hepatic vein expiratory diastolic reversal ratio ≥0.79 corresponded to a desirable combination of sensitivity (87%) and specificity (91%). The specificity increased to 97% when all 3 factors were present, but the sensitivity decreased to 64%. CONCLUSIONS: Echocardiography allows differentiation of constrictive pericarditis from restrictive myocardial disease and severe tricuspid regurgitation. Respiration-related ventricular septal shift, preserved or increased medial mitral annular e' velocity, and prominent hepatic vein expiratory diastolic flow reversals are independently associated with the diagnosis of constrictive pericarditis.

Symptomatic pulmonary hypertension with giant left atrial v waves after surgical maze procedures: evaluation by comprehensive hemodynamic catheterization.

BACKGROUND: The surgical maze procedure is highly effective in treating symptomatic atrial fibrillation but may have detrimental effects on left atrial (LA) contractile function and compliance. OBJECTIVE: To describe a series of patients presenting with symptomatic pulmonary hypertension due in part to LA dysfunction after surgical maze procedures. METHODS: This report includes 9 patients who (1) presented to Mayo Clinic (Rochester, MN) between 2008 and 2012 with unexplained dyspnea and pulmonary hypertension after the surgical maze procedure, (2) underwent comprehensive hemodynamic catheterization with transseptal measurement of LA pressure, (3) had large v waves on LA pressure waveforms, and (4) did not have significant mitral valve regurgitation or stenosis or pulmonary vein stenosis. RESULTS: Invasive hemodynamic assessment revealed (1) severe pulmonary hypertension (mean pulmonary pressure 47 ± 6 mm Hg), (2) severe LA hypertension (27 ± 4 mm Hg), (3) giant LA v waves (to 50 ± 8 mm Hg), (4) absence of LA or left ventricular a waves, and (5) blunted x descents (2 ± 1 mm Hg). Left ventricular end-diastolic pressure was also elevated (20 ± 5 mm Hg). CONCLUSIONS: Abnormalities in LA compliance and contractility may lead to giant LA v waves and symptomatic pulmonary hypertension after surgical maze procedures. This syndrome should be considered in the differential diagnosis for pulmonary hypertension and underscores the importance of comprehensive hemodynamic catheterization.

Modern management of acute myocardial infarction.

Disruption of intracoronary plaque with thrombus formation provides the pathophysiologic foundation for acute coronary syndromes, which comprise ST-segment myocardial infarction, non-ST-segment myocardial infarction, and unstable angina. Management differs depending on whether ST-segment elevation is present, but the general principles of timely restoration of coronary blood flow and initiation of secondary prevention strategies are applicable to all patients. The purpose of this review is to discuss first the epidemiology, pathophysiology, and diagnosis of acute myocardial infarction. Risk stratification and therapy for patients with ST-segment elevation myocardial infarction and non-ST-segment elevation acute coronary syndromes are then reviewed along with diagnosis and management of the complications of myocardial infarction.