Julio Martí-Almor

Prevalence of long QTc interval in methadone maintenance patients.

BACKGROUND There is a concern about cardiac rhythm disorders related to QTc interval prolongation induced by methadone. A cross-sectional study was designed to evaluate the prevalence of long QTc (LQTc) interval in patients in methadone maintenance treatment (MMT) and risk factors for LQTc. METHODS The study population included 109 subjects (74 males, median age 43 years). Socio-demographic and toxicological variables were recorded, as well as concomitant use of drugs related with QT prolongation, history of heart diseases, and corrected QT interval by heart rate (QTc) in the ECG. Plasma concentrations of (R)-methadone and (S)-methadone enantiomers were determined in 69 subjects. RESULTS Ten patients (9.2%) presented a QTc above 440 ms but a QTc above 500 ms was observed in only 2 (1.8%). Patients with QTc above 440 ms compared with the remaining subjects were older (median [25th-75th percentile range]: 49 [39-56] years vs. 37 [33-43]; Wilcoxons W=217.5, p=0.002) and took a higher daily dose of methadone (median [25th-75th percentile range]: 120 [66-228] mg/day vs. 60 [40-110] mg/day; W=298.5, p=0.037). Methadone dose correlated with QTc interval (Pearsons r(2)=0.291, p=0.002). Patients with and without long QTc showed no differences in plasma concentrations of (R)-methadone and (S)-methadone enantiomers. CONCLUSIONS The prevalence of LQTc was 9.2%. An association between LQTc and methadone doses was observed but the relationship with plasma concentrations of methadone enantiomers is unclear.

Obstructive Sleep Apnea in Patients With Typical Atrial Flutter: Prevalence and Impact on Arrhythmia Control Outcome

BACKGROUND The clinical yield of cavotricuspid isthmus (CTI) radiofrequency ablation of atrial flutter (AF) is limited by a high incidence of atrial fibrillation (AFib) in the long term. Among other acknowledged variables, the association of obstructive sleep apnea (OSA) could favor incomplete arrhythmia control in this setting. We assessed the impact of CPAP in reducing the occurrence of AFib after CTI ablation. METHODS Consecutive patients with AF who were undergoing CTI ablation were screened for OSA. Relationship of the following variables with the occurrence of AFib during follow-up (12 months) was investigated: CPAP initiation, hypertension, BMI, underlying structural heart disease, left atrial diameter, and AFib documentation prior to ablation. RESULTS We prospectively included 56 patients (mean age: 66 (± 11) years; 12 female patients), of whom 46 (82%) had OSA and 25 (45%) had severe OSA. Twenty-one patients (38%) had AFib during follow-up after CTI ablation. Both freedom from AFib prior to ablation and CPAP initiation in those patients without previously documented AFib at inclusion were associated with a reduction of AFib episodes during follow-up (P = .019 and P = .025, respectively). Inversely, CPAP was not protective from AFib recurrence when this arrhythmia was documented prior to ablation (P = .25). CONCLUSIONS OSA is a prevalent condition in patients with AF. Treatment with CPAP is associated with a lower incidence of newly diagnosed AFib after CTI ablation. Screening for OSA in patients with AF appears to be a reasonable clinical strategy.

Original ResearchSleep DisordersObstructive Sleep Apnea in Patients With Typical Atrial Flutter: Prevalence and Impact on Arrhythmia Control Outcome

BACKGROUND The clinical yield of cavotricuspid isthmus (CTI) radiofrequency ablation of atrial flutter (AF) is limited by a high incidence of atrial fibrillation (AFib) in the long term. Among other acknowledged variables, the association of obstructive sleep apnea (OSA) could favor incomplete arrhythmia control in this setting. We assessed the impact of CPAP in reducing the occurrence of AFib after CTI ablation. METHODS Consecutive patients with AF who were undergoing CTI ablation were screened for OSA. Relationship of the following variables with the occurrence of AFib during follow-up (12 months) was investigated: CPAP initiation, hypertension, BMI, underlying structural heart disease, left atrial diameter, and AFib documentation prior to ablation. RESULTS We prospectively included 56 patients (mean age: 66 (± 11) years; 12 female patients), of whom 46 (82%) had OSA and 25 (45%) had severe OSA. Twenty-one patients (38%) had AFib during follow-up after CTI ablation. Both freedom from AFib prior to ablation and CPAP initiation in those patients without previously documented AFib at inclusion were associated with a reduction of AFib episodes during follow-up (P = .019 and P = .025, respectively). Inversely, CPAP was not protective from AFib recurrence when this arrhythmia was documented prior to ablation (P = .25). CONCLUSIONS OSA is a prevalent condition in patients with AF. Treatment with CPAP is associated with a lower incidence of newly diagnosed AFib after CTI ablation. Screening for OSA in patients with AF appears to be a reasonable clinical strategy.

Pulmonary hemorrhage after cryoballoon ablation for pulmonary vein isolation in the treatment of atrial fibrillation.

Pulmonary vein isolation has evolved over the past years as an alternative for the treatment of symptomatic recurrences of atrial fibrillation refractory to antiarrhythmic drug treatment. Both radiofrequency energy and cryoballoon ablation have proven useful in this setting. We present the case of a 55-year-old male patient undergoing cryoballoon ablation complicated with pulmonary hemorrhage. The cause of this rare complication may be found in the damage of vascular venous structures near the ablation zone or, alternatively, in hemorrhagic damage of the pulmonary vein surrounding tissue (or less probably to direct injury of the lingular bronchus). The extremely low temperatures achieved in this case (which are often associated with deep balloon position inside the veins) are alarming and should alert the physician about the possibility of an excessively intrapulmonary vein deployment of the cryoablation balloon.

Nuevos predictores de evolución a bloqueo auriculoventricular en pacientes con bloqueo bifascicular

Introduccion y objetivos Los pacientes con bloqueo bifascicular (BBF) pueden evolucionar a bloqueo auriculoventricular (BAV) avanzado, especialmente en presencia de sincope o intervalo HV prolongado. Otras variables podrian ayudar a definir que pacientes se beneficiaran de un marcapasos (MP) profilactico. Metodos Desde 1998 hasta 2006, hemos estudiado prospectivamente a 263 pacientes consecutivos con BBF en un solo centro. Se analizaron variables clinicas, electrocardiograficas y electrofisiologicas predictoras de evolucion a BAV significativo (segundo y tercer grado). Se implantaron dispositivos de estimulacion siguiendo las guias de la Sociedad Europea de Cardiologia. Los MP fueron programados en modo VVI con frecuencia minima de 40 lat/min. Se definio necesidad de MP la presencia de BAV significativo o de estimulacion ventricular > 10%. Resultados Se incluyo a 249 pacientes (media de edad, 73,4 ± 9,3 anos; 82 mujeres). Tras una mediana de seguimiento de 4,5 (2,16-6,41) anos, se observo necesidad de MP en 102 pacientes, 45 por estimulacion > 10% y 57 por BAV significativo. Las variables que predijeron la necesidad de MP fueron presencia de sincope o presincope (hazard ratio [HR] = 2,06; intervalo de confianza [IC] del 95%, 1,03-4,12), anchura QRS > 140 ms (HR = 2,44; IC del 95%, 1,59-3,76), la insuficiencia renal (HR = 1,86; IC del 95%, 1,22-2,83) y un intervalo HV > 64 ms (HR = 6,6; IC del 95%, 4,04-10,80). La asociacion de los cuatro factores mostro una probabilidad de necesitar el MP del 95% al ano de seguimiento. Conclusiones La clinica sincopal/presincopal, el QRS > 140 ms, la insuficiencia renal y el intervalo HV > 64 ms son predictores independientes de evolucion a BAV en pacientes con BBF.

Long-term mortality predictors in patients with chronic bifascicular block.

AIMS To evaluate the long-term mortality rate and to determine independent mortality risk factors in patients with bifascicular block (BFB). Patients with BFB are known to have a higher mortality risk than the general population, not only related to progression to atrio-ventricular block but also due to the presence of malignant ventricular arrhythmias. Previous observational and epidemiological studies including a high proportion of patients with structural heart disease have shown an important cardiac mortality rate and may not reflect the real outcome of patients with BFB. METHODS AND RESULTS From March 1998 until December 2006, we prospectively studied 259 consecutive BFB patients, 213 (82%) of whom presenting with syncope/pre-syncope, undergoing electrophysiological study. After a median follow-up of 4.5 years (P25:2.16-P75:6.41), 53 patients (20.1%) died, 19 (7%) of whom due to cardiac aetiology. Independent total mortality predictors were age [hazard ratio (HR) 1.04, 95% confidence interval (CI) 1.01-1.09], NYHA class>or=II (HR 2.17, 95% CI 1.05-4.5), atrial fibrillation (HR 2.96, 95% CI 1.1-7.92), and renal dysfunction (HR 4.26, 95% CI 2.04-9.01). An NYHA class of >or=II (HR 5.45, 95% CI 2.01-14.82) and renal failure (HR 3.82, 95% CI 1.21-12.06) were independent predictors of cardiac mortality. No independent predictors of arrhythmic death were found. CONCLUSION Total mortality, especially of cardiac cause, is lower than previously described in BFB patients. Advanced NYHA class and renal failure are predictors of cardiac mortality.

Entrainment from the para-Hisian region for differentiating atrioventricular node reentrant tachycardia from orthodromic atrioventricular reentrant tachycardia

AIMS The difference between the stimulus-atrial and ventriculo-atrial intervals (SA-VA) and between the post-pacing interval and the tachycardia cycle length (PPI-TCL) during entrainment from the right ventricular apex distinguishes atrioventricular node reentrant (AVNRT) from orthodromic atrioventricular reentrant tachycardia (AVRT). We hypothesized that these features still apply when entrainment is performed from the para-Hisian region. METHODS AND RESULTS Forty-seven supraventricular tachycardias (34 AVNRT/13 AVRT) were included. The SA-VA and PPI-TCL were obtained in all patients by using two right-sided diagnostic catheters. In 24 of them, these measurements were also performed upon His-bundle capture during entrainment. A paced QRS widening of >or=40 ms during entrainment, when compared with the tachycardia QRS width, identified absence of His-bundle capture, P < 0.001. A SA-VA >75 ms distinguished AVNRT from AVRT, P < 0.001 (sensitivity/specificity 97%/100%). A PPI-TCL >100 ms was diagnostic of AVNRT, P < 0.001 (sensitivity/specificity 97%/92%). Upon His-bundle capture, the SA-VA and PPI-TCL shortened in AVNRT (121 +/- 23 to 66 +/- 24 ms; 139 +/- 30 to 85 +/- 31 ms, respectively, P < 0.001) and no longer differentiated AVNRT from AVRT. CONCLUSION Para-Hisian entrainment without His-bundle capture distinguishes AVNRT from AVRT with the advantage of using only two diagnostic catheters.

Effect of Permanent Atrial Fibrillation on Cognitive Function in Patients With Chronic Heart Failure.

In patients with chronic heart failure (HF), cognitive impairment (CI) is associated with poorer treatment adherence and higher readmission and mortality rates. Previous studies suggest that atrial fibrillation (AF) could impair cognitive function. This study sought to assess the association between permanent AF (permAF) and CI in patients with HF. We evaluated cognitive function in 881 patients with stable HF (73 ± 11 years, 44% women, 48% with preserved ejection fraction) using the Mini-Mental State Examination test (n = 876) and the Pfeiffers Short Portable Mental Status Questionnaire (n = 848). CI was defined as a Mini-Mental State Examination score <24 or Short Portable Mental Status Questionnaire (errors) >2. The independent association between permAF and CI was assessed by binary logistic regression analysis. A total of 295 patients (33.5%) had CI, in 5.1% of cases moderate/severe. Patients with permAF had more frequently any degree of CI (43% vs 31%), and moderate/severe CI (8% vs 5%). In the multivariate analysis, CI was associated with permAF (odds ratio 1.54, 95% C.I. 1.05 to 2.28), an older age, female gender, diabetes mellitus, chronic kidney disease, previous stroke, New York Heart Association class III/IV, and lower systolic blood pressure. No interaction was found for AF and CI between patients with reduced and preserved ejection fraction. In conclusion, the presence of permAF is independently associated with CI in patients with HF, both with reduced and preserved ejection fraction. Given the clinical impact of CI in the HF population, active assessment of cognitive function is particularly warranted in patients with HF with permAF.

Novel Predictors of Progression of Atrioventricular Block in Patients With Chronic Bifascicular Block

INTRODUCTION AND OBJECTIVES Patients with chronic bifascicular block (BFB) can progress to advanced atrioventricular block (AVB), especially when syncope or a prolonged HV interval is present. It is possible that other variables could help identify patients who would benefit from prophylactic pacemaker implantation. METHODS The study involved 263 consecutive BFB patients seen at a single center between 1998 and 2006. Clinical, electrocardiographic and electrophysiologic variables were analyzed to identify predictors of progression to significant AVB (i.e. second or third grade). Cardiac pacemakers were implanted in accordance with European Society of Cardiology guidelines. Pacemakers were programmed in the VVI mode with a minimum frequency of 40 beats/min. A pacemaker was required if there was significant AVB or a ventricular pacing percentage >10%. RESULTS In total, the study included 249 patients (mean age, 73.4+/-9.3 years, 82 female). After a median follow-up period of 4.5 years (2.16-6.41 years), a pacemaker was required by 102 patients: 45 had a ventricular pacing percentage >10% and 57 had significant AVB. Factors predictive of the need for a pacemaker were: the presence of syncope or presyncope (hazard ratio [HR]=2.06; 95% confidence interval [CI], 1.03-4.12), QRS width >140 ms (HR=2.44; 95% CI, 1.59-3.76), renal failure (HR=1.86; 95% CI, 1.22-2.83), and an HV interval >64 ms (HR=6.6; 95% CI, 4.04-10.80). The presence of all four risk factors was associated with a 95% probability of needing a pacemaker within 1 year of follow-up. CONCLUSIONS The presence of syncope or presyncope, a QRS width >140 ms, renal failure, and an HV interval >64 ms were independent predictors of progression to AVB in patients with BFB.

Simple predictors for new onset atrial fibrillation

BACKGROUND Predicting atrial fibrillation is a tremendous challenge. Only few studies have included 24h-Holter monitoring characteristics to predict new onset AF (NOAF). OBJECTIVES Our aim is to define simple predictors for NOAF. METHODS The study population included 468 patients undergoing Holter for any cause. After excluding 169 patients for history of AF prior to or during the Holter monitoring period, 299 patients were assessed for incidence of NOAF. RESULTS Age at inclusion was 62.5±18years (53.5% male). After a median follow up of 39.1 [IQI 36.6-40] months, the incidence of NOAF was 10.4%. With univariate analysis, age, hypertension, diabetes, renal impairment, heart failure/cardiomyopathy, left ventricle ejection fraction ≤50%, left atrium diameter ≥40mm, CHA2DS2 VASc ≥4, premature atrial complexes (PAC) ≥0.2%, and PR interval were associated with NOAF. With multivariate analysis, age (HR 1075; p=0.001 per year), presence of heart failure/cardiomyopathy (HR 6,16; p<0.001), PAC≥0.2% (HR 3,32; p=0.003) and PR interval (HR 1.011; p=0.006 per millisecond) were independent predictors for NOAF. Those predictors were used to create a risk calculator for NOAF, which was validated in an independent cohort of 200 consecutive patients with similar baseline characteristics. This new tool resulted in good discrimination capacity calculated by the C index for NOAF prediction: Area under curve (AUC) (95% CI) 0.794 (0.714-0.875) at 2years and 0.794 (0.713-0.875) at 3years. CONCLUSIONS Simple clinical, ECG and Holter monitoring parameters are able to predict NOAF in a broad population and may help guide more rigorous monitoring for atrial fibrillation.