[Biphasic versus monophasic shock waveforms for transthoracic cardioversion of atrial flutter in the emergency room].

UNLABELLED: Transthoracic electrical cardioversion (ECV), traditionally using monophasic waveform (MW) shock, has an important role in the treatment of symptomatic atrial flutter (AFI). Biphasic waveform (BW) shock has been demonstrated to be more successful than MW shock for termination of atrial fibrillation, but data about its use for ECV of AFI are limited. METHODS AND RESULTS: We retrospectively analyzed the records of 53 patients (pts) admitted -to the ER due to symptomatic AFl during the period August 2004 to August 2005: 31 pts received BW shock and 22 pts MW shock. The type of shock waveforms and the initial energy of CV were chosen by the doctor on duty in the ER; the lower energy for ECV was 20 joules, which was increased to 50, 100 and 200 joules if necessary. There were no significant differences between the clinical characteristics of the pts who received BW shock or MW shock. All pts underwent ECV via anterior-laterally positioned hand-held electrode paddles. Successful ECV by BW shock and MW shock was 41% and 42% of the pts, respectively, using 20 joules of energy (p=n.s.); 77% and 80% using 50 joules (p=n.s.); 93% and 90% using 100 joules (p = n.s.); 100% of successful ECV was reached when 200 joules of energy was used, regardless of waveforms type. Median energy for successful ECV was 50 joules in both types of electrical waveforms. No complications were reported. CONCLUSIONS: There were no significant differences in the success rates of conversion of atrial flutter to sinus rhythm by BW or MW shock. We recommend 50 joules for starting energy of ECV of AF1 regardless of waveforms type.

Adult calcific aortic stenosis and Chlamydia pneumoniae: the role of Chlamydia infection in valvular calcification.

BACKGROUND: Adult calcific aortic stenosis is a well-known clinical entity but its pathophysiology and cellular mechanism have yet to be defined. OBJECTIVES: To determine whether there is an association between the presence and severity of adult calcific aortic stenosis and Chlamydia pneumoniae seropositivity. METHODS: Forty adult patients (23 women, 17 men) were divided into three groups according to echocardiographic aortic valve area: Group A - 7 symptomatic subjects (age 67 +/- 7 years) with normal aortic valve and normal coronary angiogram, Group B - 16 patients (age 73 +/- 6) with moderate ACAS (AVA > 0.8 < or = 1.5 cm2), and Group C - 17 patients (age 76 +/- 7) with severe ACAS (AVA +/- 0.8 cm2). We tested for immunoglobulins M, G and A as retrospective evidence of C. pneumoniae infection using the micro-immunofluorescence method. Past C. pneumoniae infection was defined by IgG titer > 16 < or = 512. RESULTS: No patients in group A showed positive Ig for C. pneumoniae. IgM was not detected in any of the patients with ACAS (groups B and C) while 2 of 17 patients (12%) in group C showed IgA for the pathogen. High titers of IgG were found in 14 of 33 (42%) of the patients with moderate or severe ACAS: 5 of 16 (31%) in group B and 9 of 17 (53%) in group C (P = 0.2). Both groups had the same prevalence of coronary artery disease (66%). AVA was lower in IgG-seropositive patients than in the seronegative group (0.88 +/- 0.3 cm2 vs. 1.22 +/- 0.4 cm2, respectively, P = 0.02). CONCLUSIONS: Past C. pneumoniae infection may be associated with a higher prevalence and greater severity of ACAS.

[Intravenous flecainide administration for conversion of paroxysmal atrial fibrillation in the emergency room].

INTRODUCTION: Since the removal of intravenous propafenone from the Israeli market, flecainide is the only intravenous antiarrhythmic class 1C drug available nowadays in Israel. AIM: The study aimed to report our experience of intravenous flecainide administration in the treatment of paroxysmal atrial fibrillation (PAF) in the Emergency Room (ER). METHODS: Patients with AF lasting > 1 hour and <48 hour duration were considered possible candidates for entry into the study. Exclusion criteria were clinical signs of congestive heart failure, acute coronary syndrome, electrolyte imbalances, significant hepatic and renal disease, and any previously documented conduction disturbance. Flecainide was administered as a bolus dose of 2mg/kg in 10 minutes (maximum 150 mg). The patients with a ventricular response > 130 beats/min received intravenous verapamil or metoprolol in order to reduce the ventricular rate. Efficacy was defined as conversion to sinus rhythm (SR) within 120 minutes of starting medication. RESULTS: Twenty three consecutive patients were enrolled in the study. Their mean age was 60 +/- 19 years; the mean ventricular response at admission was 128 +/- 26 beats/min. SR was achieved in 10 patients (43%) after the intravenous bolus of flecainide (10 minutes) and in 17 patients (74%) 120 minutes after the beginning of the therapy. COMPLICATIONS: Hypotension (systolic blood pressure < 90 mmHg) was reported in 1 patient and QRS enlargement was seen in 1 patient. CONCLUSION: Intravenous flecainide has effective and rapid action in the conversion of PAF and its administration is safe in the treatment of this arrhythmia in the ER.

'Frozen' posterior mitral leaflet in rheumatic mitral stenosis: incidence and impact on outcome of balloon mitral commissurotomy.

BACKGROUND AND AIM OF THE STUDY: The incidence and clinical significance of immobile and 'frozen' posterior mitral leaflet (FPML) were evaluated in the pathophysiology and immediate outcome of patients with severe pliable mitral stenosis (MS) undergoing percutaneous balloon mitral commissurotomy (PBMC). METHODS: During the past four years, 30 'ideal' patients (mean age 46 +/- 8 years) with Wilkins' score <8, bilateral commissural fusion and absence of commissural calcification underwent peri-procedural echocardiographic analysis. Anterior mitral leaflet (AML) mobility index (MI), chordae tendineae (CT) length, and mitral valve area (MVA) were evaluated. RESULTS: Pre-procedure FPML was noted in 28 patients (93%). All patients achieved MVA > or = 1.5 cm2. Post-procedure MVA in patients with bilateral commissural splitting was 1.9 +/- 0.2 cm2 versus 1.6 +/- 0.1 cm2 in patients with unilateral commissural splitting (p < 0.05). CT lengths directed to the AML and PML were 15 +/- 2 mm and 8 +/- 2 mm, respectively (p < 0.05). MI of the AML before and immediately after PBMC was 0.4 and 0.6, respectively (p < 0.05). None of the patients with FPML showed improved mobility following successful PBMC. CONCLUSION: FPML may be found in most patients with pliable MS. It is mainly a result of short, rigid and fused CT directed to the PML. A 'single-wing door' or a unicuspid valve may be used as a model for rheumatic pliable MS. It is suggested that pre-procedure leaflet morphology and functional assessment should focus on the AML.

Feasibility, safety, and morphologic predictors of outcome of repeat percutaneous balloon mitral commissurotomy.

Early and mid-term results of repeat percutaneous balloon mitral commissurotomy (PBMC) were analyzed in 35 patients with symptomatic valvular restenosis: 12 patients (34%) after first successful PBMC and 23 patients (66%) after successful surgical closed mitral commissurotomy. Twenty-one patients had bilateral fused commissures, and 14 patients had unilateral or bilateral split commissures. Mitral valve area gain was significantly greater in the group with fused commissures compared with the group with split commissures (0.6 +/- 0.2 vs 0.3 +/- 0.2 cm(2), respectively, p = 0.04).

Torsade de pointes in patients on chronic amiodarone treatment: contributing factors and drug interactions.

BACKGROUND: Torsade de pointes is rarely associated with chronic amiodarone treatment, despite the effect of amiodarone on QT interval prolongation. OBJECTIVE: To identify risk factors and associated conditions that may cause TdP in patients on chronic amiodarone treatment. METHODS: We reviewed the data of six consecutive patients on chronic amiodarone treatment who were admitted to the intensive cardiac care unit due to syncope and TdP. RESULTS: The patients' median age was 73.5 years, and five were women. Concomitantly, loratadine was given to two patients and trazodone to one patient. Associated and attributing conditions to the development of TdP were hypokalemia in three patients, drug-induced bradycardia in one and reduced left ventricular function in four. CONCLUSIONS: TdP associated with chronic amiodarone treatment may occur when amiodarone is co-administered with drugs that may potentially prolong QT interval. Additional risk factors for amiodarone-associated TdP include female gender, hypokalemia, reduced left ventricular function and bradycardia.

[Biphasic shock waveform for cardioversion of atrial fibrillation in the emergency room].

UNLABELLED: Transthoracic electrical cardioversion, traditionally monophasic shock waveform, has been a mainstay of the therapy for atrial fibrillation (AF) since its introduction into clinical practice. Recent studies have demonstrated that biphasic shock is more efficient than monophasic shock waveforms for terminating both ventricular fibrillation and AF; however, data on the recommended initial shock energy in conversion of AF by biphasic shocks are limited. AIM: Our study aimed to evaluate the optimal dose of the initial shock energy for conversion of AF to sinus rhythm by transthoracic biphasic shock waveforms in the Emergency Room (ER). METHODS AND RESULTS: A total of 144 consecutive patients, who came to the ER because of AF, were our study population. All patients underwent cardioversion via anterior-laterally positioned hand-held electrode paddles. Patients received sequential shocks of 50 J (only the first 40 patients), 100 J, 150 J and 200 J if necessary. There was a significantly greater cumulative conversion success rate with 100 J (70.5%) than 50 J shock energy (55%), p < 0.05; but even greater with 150 J (89%) than 100 J shock energy, p < 0.003; no significant difference was observed between 200 J (94%) and 150 J shock energy, p < 0.58. Nine of 12 patients, whose body weight was less than 70 kg, were successfully converted to sinus rhythm (75%) by 50 J shock 1 energy. After cardioversion there were reports of: a five seconds asystole observed in 1 patient; pulmonary edema in another patient; hypotension was reported in 1 patient and mild erythema in 14 patients (9.7%). CONCLUSION: Our findings support that biphasic waveform shock energy of 150 J is advised as a first attempt, but in patients with a body weight less than 70 kg. lower energy shock may be used.

Serum antioxidant capacity and the risk of contrast medium nephropathy.

INTRODUCTION: The use of contrast medium can result in an acute reduction in renal function. The exact mechanism of this side effect is not yet fully understood. There is accumulating evidence that reactive oxygen species have a role in renal damage. Prophylactic administration of antioxidant drugs could prevent this reduction in renal function. We examined whether there is a correlation between the antioxidant capacity of the serum and the risk of contrast medium nephropathy. METHODS: We studied prospectively 193 patients with normal renal function who underwent cardiac catheterization. Serum haptoglobin, uric acid, albumin and the total antioxidant capacity were measured before the injection of contrast media. Serum urea and creatinine concentrations were measured before angiography and on days 3 and 7 following the procedure. RESULTS: Eleven patients developed mild renal failure. We compared the serum levels of antioxidant compounds of this group with the serum levels of these compounds in patients who did not develop renal damage. No statistical significant difference in the baseline levels of antioxidant species was found between the two groups. CONCLUSIONS: These prospective data indicate that among low-risk patients with normal renal function, baseline levels of antioxidant material did not predict the possible development of contrast medium nephropathy.

Utility and diagnostic accuracy of hand-carried ultrasound for emergency room evaluation of chest pain.

This study examined the utility and accuracy of immediate hand-carried echocardiography in patients presenting to the emergency room with chest pain and a normal or nondiagnostic electrocardiogram. Hand-carried echocardiography was highly concordant (kappa = 0.8) with troponin T tests as well as the discharge diagnosis of acute coronary syndrome, had a 100% sensitivity for the detection of acute coronary syndrome, 93% specificity, and 71% and 100% positive and negative predictive values, respectively.

Massive transient pulmonary air embolism during pacemaker implantation under mild sedation: an unrecognized hazard of snoring.

We present a case of a massive pulmonary air embolism during permanent pacemaker lead implantation under mild sedation in a 73-year-old woman. We used a peel-away sheath that is devoid of a hemostatic valve. The air embolism occurred after deep inspiration associated with loud snoring sounds and resolved after short chest massage and administration of adrenaline. Temporary closure of the intravenous entrance route of the peel-away sheath before inserting the lead may prevent this potentially lethal complication.

Unsuccessful rescrewing of a dislodged screw-in atrial lead.

We report a case of unsuccessful rescrewing of an atrial lead after its early dislodgment in a 64 years old patient because of entrapped endocardial tissue in the screw-in system.

Incidence of postdischarge symptomatic paroxysmal atrial fibrillation in patients who underwent coronary artery bypass graft: long-term follow-up.

The aim of this retrospective study was to determine the incidence of symptomatic AF of patients who had undergone coronary artery bypass grafting (CABG) during long-term follow-up. The study population included 305 post-CABG patients who were regularly followed in the outpatient clinic. Paroxysmal AF (PAF) was defined as an episode of symptomatic AF when symptoms were prolonged enough for the patient to request medical care. Perioperative AF occurred in 88 (28.9%) patients. Postdischarge symptomatic PAF occurred in 25 (8.2%) patients with an annual incidence of 2% during a mean follow-up of 48 +/- 30 months. Eighteen (20.4%) patients also experienced perioperative AF with an annual incidence of 5.1%, while only 7 (3.2%) of 217 patients, without perioperative AF, had postdischarge AF (P < 0.0003). During long-term follow-up, postdischarge AF has a low incidence and prophylactic antiarrhythmic therapy is not recommended. The method of follow-up and retrospective analysis may understate PAF and even miss some symptomatic episodes. Perioperative AF is a predictor of symptomatic late PAF recurrences, particularly in patients with reduced left ventricular function.

[Intravenous propafenone for conversion of atrial fibrillation in the emergency room].

Atrial fibrillation (AF) is the most common sustained symptomatic arrhythmia encountered in the emergency room (ER). Rapid, safe and effective conversions of AF to sinus rhythm (SR) are important aspects in the treatment of arrhythmia in a busy ER setting. The aim of our study was to investigate the rate of conversion, efficacy and safety of intravenous (i.v.) propafenone administration for the treatment of AF in the ER. Seventy five patients (pts), admitted in the ER with symptomatic AF were randomized to receive propafenone or placebo: 40 pts received propafenone as an i.v. bolus of 2 mg/kg in 15 minutes, followed by maintenance infusion of 0.0067 mg/kg/min until conversion to SR or for up to 90 minutes (Group 1). The matching placebo (an equal volume of saline solution) was administered to 35 pts in the same fashion (Group 2). Direct current (DC) cardioversion was attempted in pts still in AF 15 minutes after infusion administration was terminated. SR was achieved in 24 pts treated with propafenone (60%) versus 10 pts treated with placebo (29%) (p<0.02) and the median conversion time was 15 minutes versus 105 minutes respectively (p<0.001). None of the pts who were in AF for more than 48 hours were converted to SR by infusion. Five patients had mild and transient adverse event during propafenone treatment versus none with placebo (p=ns). Therefore, we conclude that i.v. administration of propafenone in the ER is an effective, rapid and safe therapeutic alternative for pts with symptomatic AF.

Percutaneous balloon mitral valvuloplasty in patients with severe mitral stenosis and low transmitral diastolic pressure gradient.

An elevated left atrial pressure and high diastolic pressure gradient (DPG) across the mitral valve are the major hemodynamic abnormalities in mitral stenosis (MS). However, a subgroup of patients with severe MS is characterized by low initial DPG. The authors reviewed the clinical, echocardiographic and hemodynamic data as well as procedural results in 180 patients who underwent percutaneous balloon mitral valvuloplasty (PBMV). An initial mean DPG > 10 mmHg was found in 144 patients (80%) (group A) and mean DPG < or = 10 mmHg in 36 patients (20%) (group B). Patients in group A had higher left ventricular ejection fraction (LVEF) than in group B (61 +/- 5% versus 42 +/- 6%, respectively) and higher cardiac index (2.8 +/- 0.4 versus 2.0 +/- 0.3 l/min/m(2) ). In group B 12 patients (33%) had normal LVEF, whereas 24/36 (67%) had reduced LVEF. All the latter had wall motion abnormalities on ventriculography. Unlike group A, intraprocedural echocardiography was essential for monitoring and evaluating immediate results of PBMV in group B. On follow-up of three years, 75% of group A patients and 55% in group B were in functional class I (p < 0.05). PBMV did not significantly improve symptoms in patients in group B who had preprocedure LVEF < or = 35%.

The subvalvular apparatus in rheumatic mitral stenosis: methods of assessment and therapeutic implications.

The assessment of the structure and function of the subvalvular apparatus (SVA) in patients with rheumatic mitral stenosis (MS) is complex, yet is of major importance prior to therapeutic decision making. Currently available methods of assessment are neither sufficiently accurate nor feasible. We review anatomic and functional aspects of the SVA and define SVA involvement in rheumatic MS. The role of various noninvasive and invasive methods for evaluating the integrity and function of SVA in rheumatic MS, as well as clinical implications and pitfalls in assessment of SVA are also discussed.

Transient cardiac dysfunction and pulmonary edema in exertional heat stroke.

Exertional heat stroke is a medical emergency that uncommonly results in severe cardiac dysfunction. The military physician diagnosed a 19-year-old military recruit from an elite unit to have exertional heat stroke. Immediate treatment in the field with rapid ice water cooling and vigorous fluid administration resulted in pulmonary edema. Transthoracic echocardiography on admission to the emergency department revealed moderate reduction in left and right ventricular function. After treatment, within a few days, rapid myocardial recovery was noted and persisted after 6 months of follow-up. Possible mechanisms of cardiac dysfunction in exertional heat stroke and treatment strategies are discussed. It is suggested that intravenous fluid administration to patients with suspected exertional heat stroke should preferably be done with appropriate hemodynamic monitoring and after cardiac dysfunction has been ruled out.

Torsades de pointes and QT prolongation due to a combination of loratadine and amiodarone.

Torsades de pointes (TdP) has not been previously reported with loratadine. A 73-year old woman on chronic treatment with amiodarone for atrial fibrillation received loratadine and presented with syncope and multiple episodes of TdP. We suggest that QT interval should be monitored whenever loratadine is co-administered with drugs that may potentially prolong QT.