Termination of Sustained Ventricular Fibrillation During Radiofrequency Catheter Ablation.

After a ST-segment elevation inferior myocardial infarction, a patient developed multiple drug-refractory ventricular fibrillation (VF), triggered by a stereotypic premature ventricular complex. During an episode of sustained VF, catheter ablation of the moderator band terminated VF, with transition into monomorphic ventricular tachycardia. To the best of our knowledge, this is the first-in-human report of termination of VF during delivery of radiofrequency energy, which suggests that the focal area on moderator band of Purkinje system had an active role in the perpetuation of VF. (Level of Difficulty: Advanced.).

Refractory Ventricular Tachycardia Originating From an Intracardiac Metastasis Treated With Catheter Ablation.

A 45-year-old man with stage IV melanoma presented with incessant nonsustained wide complex tachycardia. He was found to have a right ventricular intracardiac metastasis that created a nidus for ventricular tachycardia refractory to multiple therapeutic interventions. The patient underwent catheter ablation for this rare indication, with successful arrhythmia control by direct ablation over the tumor surface. (Level of Difficulty: Advanced.).

Prospective Validation of PREDICT and Its Impact on the Transesophageal Echocardiography Use in Management of Staphylococcus aureus Bacteremia.

BACKGROUND: Infective endocarditis (IE) is the most feared complication of Staphylococcus aureus bacteremia (SAB). Transesophageal echocardiogram (TEE) is generally recommended for all patients with SAB; however, supporting data for this are limited. We previously developed a scoring system, "PREDICT," that quantifies the risk of IE and identifies patients who would most benefit most from undergoing TEE. The current prospective investigation aims to validate this score. METHODS: We prospectively screened all consecutive adults (≥18 years) hospitalized with SAB at 3 Mayo Clinic sites between January 2015 and March 2017. RESULTS: Of 220 patients screened, 199 with SAB met study criteria and were included in the investigation. Of them, 23 (11.6%) patients were diagnosed with definite IE within 12 weeks of initial presentation based on modified Duke's criteria. Using the previously derived PREDICT model, the day 1 score of ≥4 had a sensitivity of 30.4% and a specificity of 93.8%, whereas a day 5 score of ≤2 had a sensitivity and negative-predictive value of 100%. Additional factors including surgery or invasive procedure in the past 30 days, prosthetic heart valve, and higher number of positive blood culture bottles in the first set of cultures were associated with increased risk of IE independent of the day 5 risk score. CONCLUSIONS: We validated the previously developed PREDICT scoring tools for stratifying risk of IE, and the need for undergoing a TEE, among cases of SAB. We also identified other factors with predictive potential, although larger prospective studies are needed to further evaluate possible enhancements to the current scoring system.

Left atrial appendage exclusion during mitral valve surgery and stroke in atrial fibrillation.

PURPOSE: The purpose of this study was to determine whether surgical left atrial appendage (LAA) exclusion performed during mitral valve surgery is associated with a reduction in cerebrovascular events in patients with atrial fibrillation. METHODS: We retrospectively studied patients with atrial fibrillation who underwent mitral valve surgery from 1/1/2001 through 12/31/2014. We screened 1352 patients using ICD-9 codes and included 281 patients in the study. The primary end point was a composite of strokes and transient ischemic attacks occurring within 5 years after surgery. Secondary end points were stroke, transient ischemic attack, and all-cause mortality. RESULTS: The LAA exclusion group (n = 188) had a lower prevalence of female gender, hypertension, and diabetes mellitus compared with the non-LAA exclusion group (n = 93). The CHA2DS2VASc scores were comparable between groups (2.6 vs 2.9, P = .11), as was anticoagulant use (82.4% vs 85.0%, P = .60). Concomitant surgical ablation was performed in 73.9% of patients who underwent LAA exclusion. Nine cerebrovascular events occurred in the LAA exclusion group and 13 in the non-LAA exclusion group (HR 0.30 [0.12-0.75], P = .01). There was no difference in all-cause mortality between groups. On multivariate analysis of the primary end point of strokes or transient ischemic attacks, significant variables were LAA exclusion (HR 0.31 [0.12-0.76], P = .01) and CHA2DS2VASc score (HR 1.44 [1.11-1.87], P = .006). The benefit of LAA exclusion was detected only when performed together with surgical ablation (HR 0.27 [0.09-0.72], P = .01). CONCLUSIONS: LAA exclusion was associated with fewer cerebrovascular events. However, this benefit was seen only with concomitant surgical ablation.

Comparison of Dual ß-Lactam therapy to penicillin-aminoglycoside combination in treatment of Enterococcus faecalis infective endocarditis.

BACKGROUND: Dual ß-lactam therapy and a penicillin-aminoglycoside combination are first line regimens in the treatment of penicillin-susceptible Enterococcus faecalis infective endocarditis (EFIE). Our aim was to compare ampicillin plus ceftriaxone (A+C) to ampicillin plus gentamicin (A+G) in the treatment of EFIE. METHODS: This was a retrospective cohort study of adults (≥18 years) patients diagnosed with EFIE at Mayo Clinic campuses in Rochester, Minnesota, and Phoenix, Arizona and treated with either A+C or A+G. Main outcome measurements were 1 year mortality, nephrotoxicity, and EFIE relapse rates. RESULTS: Eighty-five cases of EFIE were included in this investigation. The majority (n=67, 79%) of patients received A+G while 18 (21%) patients received A+C as initial treatment. On admission, patients who received A+C had a higher Charlson Comorbidity Index (median [IQR], 4 [3, 4 vs. 2 [1, 4]; P=.008) and a higher baseline serum creatinine (median [IQR], 1.2 [0.9, 1.6] vs. 0.9 [0.8, 1.2] mg/dL, P=.020). The 1 year mortality rates were similar for both treatment groups, 17% vs. 17%, P=.982. Each group had 1 case of relapsing EFIE. Patients who received A+G had worse kidney function outcome demonstrated by a greater increase in serum creatinine at end of therapy (median [IQR] difference, +0.4 [0.2, 0.8] vs. -0.2 [-0.3, 0.1] mg/dL, P≤.001). CONCLUSION: A+C appears to be a safe and efficacious regimen in the treatment of EFIE. Patients treated with A+C had lower rates of nephrotoxicity and no differences in relapse rate and 1-year mortality as compared to that of the A+G group.

Handheld Echocardiography Saves the Brain: A Serendipitously Found Left Ventricular Thrombus.

Handheld echocardiography (HHE) is an emerging technology with potential to alter routine clinical practice. Our institution has adopted the use of HHE devices for both teaching and patient care. However, the appropriate clinical scope of HHE continues to be controversial, and the literature is largely devoid of prognosis-altering applications. We report the diagnosis of left ventricular (LV) thrombus with HHE. A 75-year-old man presented with a large anteroapical ST-elevation myocardial infarction (MI). Initial transthoracic echocardiography (TTE) after percutaneous intervention showed no LV thrombus. Before his hospital discharge, HHE was performed and showed LV thrombus. The finding substantially changed the patient's treatment and prognosis; he was discharged with warfarin. This observation will help guide further inquiry into the proper clinical role of HHE.

Managing the patient with episodic sinus tachycardia and orthostatic intolerance.

Patients with episodic sinus tachycardia and associated orthostatic intolerance present a diagnostic and management dilemma to the clinician. We define this group of disorders to include sinus node reentrant tachycardia (SNRT), inappropriate sinus tachycardia (IAST), and postural orthostatic tachycardia syndrome (POTS). After a brief review of the current understanding of the pathophysiology and epidemiology of this group of disorders, we focus on the diagnosis and management of IAST and POTS. Our approach attempts to recognize the considerable overlap in pathophysiology and clinical presentation between these two heterogeneous conditions. Thus, we focus on a mechanism-based workup and therapeutic approach. Sinus tachycardia related to identifiable causes should first be ruled out in these patients. Next, a basic cardiovascular and autonomic workup is suggested to exclude structural heart disease, identify a putative diagnosis, and guide therapy. We review both nonpharmacologic and pharmacologic therapy, with a focus on recent advances. Larger randomized control trials and further mechanistic studies will help refine management in the future.