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Brian Olshansky

Publications and source records attributed to Brian Olshansky.

12 recordsLinked to original sources

Irregular atrial activation during atrioventricular nodal reentrant tachycardia: evidence of an upper common pathway.

Controversy continues regarding the precise nature of the reentrant circuit of AV nodal reentrant tachycardia, especially the existence of an upper common pathway. In this case report, we show that marked variation and irregularity in atrial activation (maximum AA interval variation of 80 msec) can exist with fixed and constant activation of the His bundle and ventricles during AV nodal reentrant tachycardia in a 45-year-old female patient. We propose that irregular atrial activation is due to variable and inconsistent conduction from the AV node to the atria through the perinodal transitional cell envelope extrinsic to the reentrant circuit. Our observations support the concept of an upper common pathway, at least in some patients with AV nodal reentrant tachycardia.

Cardiotonic Agents↗

Outpatient cardioversion of atrial arrhythmias: efficacy, safety, and costs.

BACKGROUND: Outpatient direct current (DC) cardioversion is performed routinely, yet scant data support this approach. We studied the efficacy, safety, and costs of outpatient cardioversion. METHODS: A retrospective analysis of outpatient cardioversions was performed in a 5-year period at an academic medical center in 532 consecutive outpatients with an atrial tachyarrhythmia. The protocol included anticoagulation (international normalized ratio >or=2.0) for >or=4 consecutive weekly draws and then DC cardioversion with the patient under intravenous anesthesia. Arrhythmia symptoms, antiarrhythmic therapy use, and costs were evaluated. RESULTS: Ninety percent of patients were discharged in sinus rhythm after cardioversion with a median number of shocks of 1 (range, 1-6) for atrial flutter (n = 113), atrial tachycardia (n = 13), and atrial fibrillation (n = 406). Sixty-seven percent of patients were treated with an antiarrhythmic drug. The complication rate was 2.6%, with 11 unplanned admissions. Thromboemboli occurred only in patients whose anticoagulation deviated from protocol and included chronic hemianopsia starting 4 days after cardioversion, transient right-sided weakness, and cerebral vascular accident 3 days after cardioversion, despite negative results on a transesophageal echocardiogram. Two patients had postcardioversion pulmonary edema. Bradycardia developed in 4 patients; transient pacemaker noncapture after the shock occurred in 4 patients. Transient postshock rhythms also included AV nodal Wenckebach and junctional rhythm. One patient had aspiration pneumonia. The mean cost of cardioversion was 464 dollars. Fees for anesthesia ranged from 525 dollars to 650 dollars. The anesthetic costs ranged from 2.84 dollars to 21.47 dollars. The cardiology fee averaged 501 dollars. CONCLUSION: Outpatient cardioversion is a low risk, effective, and economical procedure.

Adolescent↗

Early versus late atrial fibrillation after atrial flutter ablation.

INTRODUCTION: Radiofrequency catheter ablation of atrial flutter (AFl) has high initial success with a 10-15% recurrence. Atrial fibrillation (AFib) after radiofrequency catheter ablation of AFl can occur but may be transient (lasting no more than four weeks). METHODS: Of one hundred seventeen consecutive patients studied, one hundred and four consecutive patients with sustained, symptomatic AFl, as the predominant rhythm disturbance (some of whom had transient pre-ablation AFib), referred for radiofrequency catheter ablation, had clinical follow-up. All had evidence for successful AFl ablation. Patients were followed prospectively. RESULTS: Over a mean follow-up of 28 months, 28 patients developed AFib after ablation of AFl [12 early AFib (<2 months) and 16 late AFib (>2 months)]. Seven of 12 (58%) patients in the early onset group reverted to normal sinus rhythm; none required long-term antiarrhythmic therapy. Only one (8%) developed permanent AFib. No patient in the late onset group remained in sinus rhythm without an antiarrhythmic drug. Three (19%) developed permanent AFib despite therapy among those with late onset AFib. Two (17%) patients with early onset AFib reverted to normal sinus rhythm with treatment versus 5 (31%) in the late onset group. Finally, only 2 patients (17%) with paroxysmal/persistent episodes of Afib from the early onset group stayed in normal sinus rhythm despite therapy, while 8 patients (50%) with paroxysmal/persistent AFib episodes from the late onset group required therapy to maintain normal sinus rhythm. CONCLUSION: Early onset AFib after ablation of AFl is likely to be transient and self-limited. Late onset AFib after ablation of AFl can persist and require chronic therapy.

Aged↗

Implantable defibrillator use for de novo ventricular tachyarrhythmias encountered after cardiac surgery.

De novo postoperative life-threatening ventricular arrhythmias are poorly understood. Long-term benefits of, and need for, treatment is uncertain. To assess the therapeutic advantage of ICD to manage new-onset, life-threatening ventricular tachyarrhythmias after cardiac surgery. Patients included were those with an ICD implanted for de novo life-threatening ventricular tachyarrhythmias encountered 48 hours or more after cardiac surgery. Primary endpoints were total survival, time to first ICD therapy, and appropriateness of ICD therapy. Mean projected survival and projected time to first ICD therapy were calculated by the Kaplan-Meier method. Twenty-seven postoperative patients (left ventricular ejection fraction 0.22 +/- 0.07) were followed for 26 +/- 17.6 months. The index arrhythmia was sustained monomorphic ventricular tachycardia in 17 (63%) and ventricular fibrillation in 10 (37%). Electrophysiological study was positive in 22 (81%) of 27. Total survival and mean projected survival after ICD implant were 22 (81%) of 27 and 25.6 months, respectively, to end of follow-up. The majority received ICD therapy (21/27 [78%]), 20 (74%) of 27 receiving appropriate therapy. The mean time to first ICD therapy and mean projected time to first ICD therapy was 5.6 +/- 7.8 months and 10.5 months, respectively. De novo postoperative ventricular arrhythmias are associated with a high probability of late recurrence. The ICD is useful for these patients.

Adult↗

Syncope.

Successful treatment of patients with syncope depends on the accuracy of the diagnosis, because syncope is a symptom, not a disease; diagnosis of the cause for syncope therefore creates a blueprint for treatment. Most experienced practitioners can diagnose the cause of syncope for less than half of their patients. Excessive and repeat testing is expensive and may not improve the chance of a correct diagnosis. Patient history is the key to the diagnosis. Treatment may vary from a lifestyle change to open heart surgery. The great challenge of treating patients with syncope is to provide cost-effective, safe therapy to those with a benign course and still provide needed treatment for those whose syncope is life threatening.

Journal Article↗