Atrial activation mapping in sinus rhythm in the clinical electrophysiology laboratory: observations during Bachmann's bundle block.

INTRODUCTION: The high posterolateral right atrium (RA) is considered the "sinus node area," but we lack information on endocardial atrial activation in sinus rhythm. We studied RA and left atrial (LA) endocardial activation in the electrophysiology laboratory. METHODS AND RESULTS: Thirty-five patients (21 men) aged 47 +/- 16.4 years (mean +/- SD) underwent RA mapping (22.2 +/- 3.8 points). In 21 patients, LA activation was mapped (11.1 +/- 3.9 points) through the coronary sinus (CS), right pulmonary artery, and/or a patent oval foramen. Fourteen patients had atrial arrhythmias, and 3 an ECG pattern of Bachmann's bundle block. Endocardial RA activation preceded P wave in 5 (-14 +/- 4.2 ms), coincided in 11, and followed P onset in 18 (16.7 +/- 6.6 ms). Location of the zero point varied from the superior vena cava to the low RA and from lateral to paraseptal RA. In 19 patients, activation started simultaneously in 2 to 5 points located >or=1 cm apart. RA activation was descending in most, but in 3 with low onset there was collision in the anterior and septal walls. In 15 of 21 patients, descending LA activation dominated, ending in the mid CS in 12, proximal CS in 1, and simultaneously throughout the CS in 2. In 3 with Bachmann's bundle block, CS activation was ascending and in 2 double potentials were recorded from the LA roof. CONCLUSION: During stable sinus rhythm, RA activation can start in different areas or simultaneously over large areas resulting in different activation patterns, both in the RA and the LA. LA activation is predominantly descending, but in Bachmann's bundle block it becomes ascending, and double potentials suggest a location of block in the LA roof.

Atypical flutter: a review.

Understanding of typical flutter circuits led the way to the study of other forms of macroreentrant tachycardias of the atria, and to their treatment by catheter ablation. It has become evident that the ECG classification of atrial flutter and atrial tachycardia by a rate cutoff and the presence or absence of isoelectric baselines between atrial deflections is not a valid indicator of tachycardia mechanism. Macroreentrant circuits where activation rotates around large obstacles are the most common arrhythmias found in patients with atypical forms of flutter or atrial tachycardia, especially after surgery for congenital heart disease, however, focal mechanisms can also be found. Large areas of low voltage electrograms, suggestive of severe myocardial damage (fibrosis or infiltration) can be found in many atypical macroreentrant tachycardias at the center of the circuit. Many of these circuits can be mapped precisely, critical isthmuses can be defined, and effective catheter ablation can be performed. The need to match activation maps with anatomy precisely, makes computer assisted, anatomically precise mapping a useful tool. Entrainment techniques have to be used sparingly to avoid tachycardia interruption. In complex cases, ablation can be done in sinus rhythm, after definition of conducting channels between low voltage areas and scars or anatomic obstacles. Long-term prognosis is uncertain and depends on the underlying pathology.

[Hand-held echocardiographic devices: what do they add to the initial cardiovascular evaluation?]. / Ecocardiograma portátil: ¿qué añade a la valoración cardiovascular inicial?

INTRODUCTION AND OBJECTIVES: Hand-held echocardiographic devices have recently become available. Our objective was to determine, on the basis of clinical data and basic diagnostic techniques, whether hand-held devices offer additional information useful not provided by the initial cardiovascular diagnosis. PATIENTS AND METHOD: We prospectively studied the presence and severity (absent, mild, significative) of 7 frequent heart diseases (aortic or mitral stenosis-regurgitation, tricuspid regurgitation, and left ventricular systolic dysfunction-hypertrophy) in 36 consecutive patients (50% men; mean age 68 12 years) with 3 different methods: clinical examination and basic complementary exams, hand-held echocardiography with 2D and color Doppler imaging (OptiGo, Philips Medical Systems, The Netherlands) and a standard, last-generation transthoracic echocardiogram (Sonos 550, Philips Medical Systems, The Netherlands). We compared the results obtained with the first two methods, and combined the results of both to compare these findings against the results obtained with standard electrocardiography. Percentage agreement and Somer's D, a measure of association between ordinal variables, were calculated. RESULTS: The hand-held device obtained better results than clinical examination (agreement 87 vs. 65%; D = 0.79 0.04 vs. 0.19 0.53) and identified severe lesions that were classified incorrectly by clinical examination in 39% (14/36) patients. However, in 8 patients (10 evaluations) it misclassified severe lesions. CONCLUSIONS: In experienced hands, a hand-held echocardiographic device offers additional information not obtained from an initial cardiovascular diagnosis for common cardiovascular disorders, but it is no substitute for complete echocardiographic examination.

Ecocardiograma portátil: ¿qué añade a la valoración cardiovascular inicial? / Hand-held echocardiographic devices: what do they add to the initial cardiovascular evaluation?

Introducción y objetivos. Desde hace poco tiempo disponemos de nuevos sistemas portátiles de ecocardiografía. Nuestro objetivo es determinar si un ecocardiograma portátil aporta información suplementaria al diagnóstico cardiovascular inicial, basado en datos clínicos y técnicas diagnósticas básicas. Pacientes y método. Estudiamos prospectivamente la presencia y severidad (ausente, leve, significativa) de 7 cardiopatías frecuentes: estenosis-insuficiencia aórtica y mitral, insuficiencia tricuspídea y disfunción-hipertrofia ventricular izquierda en pacientes consecutivos mediante 3 técnicas distintas: valoración clínica junto con pruebas complementarias básicas, ecocardiograma portátil con imagen 2D y Doppler color (Optigo®, Philips Medical Systems) y ecocardiograma estándar de última generación (Sonos 5500®, Philips Medical Systems). Comparamos los resultados obtenidos mediante las primeras 2 técnicas y combinando los resultados de ambas, respecto al ecocardiograma estándar, mediante el porcentaje de concordancia y la medida de asociación D de Somers. Resultados. Estudiamos a 36 pacientes (50 por ciento varones; edad, 68 ñ 12 años). El ecocardiograma portátil obtuvo mejores resultados que la valoración clínica (concordancia del 87 frente al 65 por ciento; D = 0,79 ñ 0,04 frente a 0,19 ñ 0,53) e identificó lesiones significativas incorrectamente valoradas por la clínica en un 39 por ciento (14/36) de los pacientes; sin embargo, en 8 pacientes (10 valoraciones) valoró erróneamente lesiones significativas. Conclusiones. El ecocardiograma portátil, en manos experimentadas, aporta información adicional al diagnóstico inicial de enfermedades cardiovasculares comunes, pero no resulta equivalente a un diagnóstico ecocardiográfico completo (AU)