Jordi Bruguera-Cortada

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.

Punto de corte óptimo de NT-proBNP para el diagnóstico de insuficiencia cardiaca mediante un test de determinación rápida en atención primaria

INTRODUCTION AND OBJECTIVES Measurement of natriuretic peptides may be recommended prior to echocardiography in patients with suspected heart failure. Cut-off point for heart failure diagnosis in primary care is not well established. We aimed to assess the optimal diagnostic cut-off value of N-terminal pro-B-type natriuretic peptide on a community population attended in primary care. METHODS Prospective diagnostic accuracy study of a rapid point-of-care N-terminal pro-B-type natriuretic peptide test in a primary healthcare centre. Consecutive patients referred by their general practitioners to echocardiography due to suspected heart failure were included. Clinical history and physical examination based on Framingham criteria, electrocardiogram, chest X-ray, N-terminal pro-B-type natriuretic peptide measurement and echocardiogram were performed. Heart failure diagnosis was made by a cardiologist blinded to N-terminal pro-B-type natriuretic peptide value, using the European Society of Cardiology diagnosis criteria (clinical and echocardiographic data). RESULTS Of 220 patients evaluated (65.5% women; median 74 years [interquartile range 67-81]). Heart failure diagnosis was confirmed in 52 patients (23.6%), 16 (30.8%) with left ventricular ejection fraction <50% (39.6 [5.1]%). Median values of N-terminal pro-B-type natriuretic peptide were 715 pg/mL [interquartile range 510.5-1575] and 77.5 pg/mL [interquartile range 58-179.75] for patients with and without heart failure respectively. The best cut-off point was 280 pg/mL, with a receiver operating characteristic curve of 0.94 (95% confidence interval, 0.91-0.97). Six patients with heart failure diagnosis (11.5%) had N-terminal pro-B-type natriuretic peptide values <400 pg/mL. Measurement of natriuretic peptides would avoid 67% of requested echocardiograms. CONCLUSIONS In a community population attended in primary care, the best cut-off point of N-terminal pro-B-type natriuretic peptide to rule out heart failure was 280 pg/mL. N-terminal pro-B-type natriuretic peptide measurement improve work-out diagnoses and could be cost-effectiveness.

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.

Diagnostic and Prognostic Value of Electrophysiologic Study in Patients With Nondocumented Palpitations

The 12-lead electrocardiogram helps to define the arrhythmic mechanism in patients with palpitations. However, in the setting of nondocumented palpitations the value of the electrophysiologic study (EPS) needs additional investigation. We investigated the utility of the EPS in patients with nondocumented palpitations. A total of 172 patients with normal electrocardiographic findings and nondocumented palpitations underwent an EPS. The clinical and electrophysiologic characteristics were assessed. The symptoms were long-lasting (>5 minutes) in 56%. Sudden onset was present in 99%, and termination was rapid in 65%. Neck palpitations were reported in 36%. The EPS findings were normal in 86 patients (50%); atrioventricular nodal reentrant tachycardia was induced in 43, orthodromic reentrant tachycardia in 9, and nonsustained atrial tachycardia/fibrillation (AT/AF) in 34. Long-lasting episodes, sudden termination, and neck palpitations predicted positive EPS findings and were associated with reentrant supraventricular tachycardia (p<0.001). The induction of AT/AF was associated with age >50 years and structural heart disease (p<0.001). After 53 ± 36 months of follow-up, 92% of patients with negative EPS findings were symptom free. Only 32% of patients with induced AT/AF remained free of symptoms (p<0.001). The recurrence of palpitations was more prevalent among patients with structural heart disease and aged >50 years (p<0.001). In conclusion, 50% of patients with nondocumented palpitations had positive EPS findings. A long duration, sudden termination, and neck palpitations, together with structural heart disease and age >50 years, predicted tachycardia inducibility and recurrence and could help in selecting patients suitable for EPS and ablation.

Impacto a largo plazo del tratamiento con presión positiva continua en la vía aérea superior sobre la incidencia de arritmias y la variabilidad de frecuencia cardiaca en pacientes con apnea del sueño

INTRODUCTION Autonomic dysfunction can alter heart rate variability and increase the incidence of arrhythmia. We analyzed the impact of continuous positive airway pressure (CPAP) on this pathophysiological phenomenon in patients with severe sleep apnea-hypopnea syndrome. METHODS Consecutive patients with recently diagnosed severe sleep apnea-hypopnea syndrome were prospectively considered for inclusion. Incidence of arrhythmia and heart rate variability (recorded on a 24-hour Holter monitoring device) were analyzed before starting CPAP therapy and 1 year thereafter. RESULTS A total of 26 patients were included in the study. CPAP was administered for 6.6 ± 1.8 hours during Holter monitoring. After starting CPAP, we observed a marginally significant reduction in mean HR (80 ± 9 to 77 ± 11 bpm, p=.05). CPAP was associated with partial modulation (only during waking hours) of r-MSSD (p=.047) and HF (p=.025) parasympathetic parameters and LF (p=.049) sympathetic modulation parameters. None of these parameters returned completely to normal levels (p<.001). The number of unsustained episodes of atrial tachycardia diminished (p=.024), but no clear effect on other arrhythmias was observed. CONCLUSIONS CPAP therapy only partially improves heart rate variability, and exclusively during waking hours, and reduces incidence of atrial tachycardia, both of which can influence cardiovascular morbidity and mortality in sleep apnea-hypopnea syndrome patients.

Atrial Tachycardia Originating From the Pulmonary Vein: Clinical, Electrocardiographic, and Differential Electrophysiologic Characteristics

INTRODUCTION AND OBJECTIVES Although atrial tachycardia (AT) frequently originates in the pulmonary vein, pulmonary vein atrial tachycardia (PV-AT) can be difficult to recognize on an ECG. The aim of this study was to identify clinical and electrophysiologic characteristics specific to PV-AT, including sinus P-wave duration and notching. METHODS The study included 87 patients who underwent AT ablation, divided into four groups: those with PV-AT alone (Group 1, n=25), those with PV-AT associated with atrial fibrillation (Group 2, n=18), and those with other forms of left AT (Group 3, n=7) and right AT (Group 4, n=37). RESULTS The mean age of patients in Group 1, at 44 + or - 14 years, was less than in Groups 2, 3 and 4, at 57 + or - 9, 58 + or - 12 and 53 + or - 16 years, respectively (P< .05) and the left atrial diameter, at 38 + or - 4 mm, was less than in the other left AT groups: 48 + or - 7 mm in Group 2 and 49 + or - 5 mm in Group 3 (P< .05). Overall, PV-AT was most frequently due to abnormal automaticity or triggered activity (P< .05) and presented with a short cycle length: 289 + or - 45 ms and 280 + or - 48 ms in Groups 1 and 2, respectively, versus 392 + or - 106 ms and 407 + or - 87 ms in Groups 3 and 4, respectively (P< .05). In patients aged <50 years with AT and no underlying heart disease, PV-AT was significantly (P< .05) associated with a P-wave duration > or = 110 ms (sensitivity 68%, specificity 69%) and P-wave notching (sensitivity 79%, specificity 70%). CONCLUSIONS Sinus P-wave prolongation and notching in young patients with a rapid AT but without heart disease predicted an origin in the pulmonary vein.

Eficacia antianginosa de la ivabradina. Mecanismos de acción diferenciales con otros fármacos antianginosos

La reduccion de la frecuencia cardiaca es un instrumento basico en el tratamiento de la angina cronica estable, con efectos tanto en los sintomas como en el pronostico. Los bloqueadores beta, y en menor medida los calcioantagonistas no dihidropiridinicos, ejercen parte de su eficacia antianginosa por este mecanismo. La ivabradina inhibe de forma selectiva la corriente If en las celulas del nodo sinusal y logra una marcada prolongacion del tiempo de despolarizacion diastolica espontanea y, con ello, una significativa reduccion de la frecuencia cardiaca, tanto en reposo como durante el ejercicio, sin otros efectos hemodinamicos, a diferencia de los antagonistas del calcio o los bloqueadores beta, y con potencia similar a la de estos. Los estudios en voluntarios sanos y en angina de esfuerzo cronica estable limitante han demostrado la eficacia frente a placebo con diferentes dosis. En comparacion con los bloqueadores beta o antagonistas del calcio, o combinada con ellos, tambien se ha objetivado una franca mejoria de los sintomas anginosos y una mayor tolerancia al esfuerzo.