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Abstract In this article, we will comment on new aspects of P‐wave morphology that help us to better diagnose atrial blocks and atrial enlargement, and their clinical implications. These include: (1) Atypical ECG patterns of advanced interatrial block; (2) The ECG diagnosis of left atrial enlargement versus interatrial block; (3) Atrial fibrillation and advanced interatrial block: The two sides of the same coin; and (4) P‐wave parameters: Clinical implications.

Abstract The two most common modes of death among chronic heart failure (CHF) patients are sudden cardiac death (SCD) and pump failure death (PFD). Periodic repolarization dynamics (PRD) quantifies low-frequency oscillations in the T wave vector of the electrocardiogram (ECG) and has been postulated to reflect sympathetic modulation of ventricular repolarization. This study aims to evaluate the prognostic value of PRD to predict SCD and PFD in a population of CHF patients. 20-min high-resolution (1000 Hz) ECG recordings from 569 CHF patients were analyzed. Patients were divided into two groups, $$\hbox {PRD}^+$$ PRD + and $$\hbox {PRD}^-$$ PRD - , corresponding to PRD values above and below the optimum cutoff point of PRD in the study population. Univariate Cox regression analysis showed that SCD risk in the $$\hbox {PRD}^+$$ PRD + group was double the risk in the $$\hbox {PRD}^-$$ PRD - group [hazard ratio (95% CI) 2.001 (1.127–3.554), $$\hbox {p}

Interatrial blocks like other types of block may be of first degree or partial second degree, also named transient atrial block or atrial aberrancy, and third degree or advanced. In first degree, partial interatrial block (P-IAB), the electrical impulse is conducted to the left atrium, through the Bachmann’s region, but with delay. The ECG shows a P-wave ≥ 120 ms. In third-degree, advanced interatrial block (A-IAB), the electrical impulse is blocked in the upper part of the interatrial septum (Bachmann region); the breakthrough to LA has to be performed retrogradely from the AV junction zone. This explains the p ± in leads II, III and aVF. In typical cases of A-IAB, the P-wave morphology is biphasic (±) in leads II, III and aVF, because the left atrium is activated retrogradely and, therefore, the last part of the atrial activation falls in the negative hemifield of leads II, III and aVF. Recently, some atypical cases of A-IAB have been described. The presence of A-IAB is a risk factor for atrial fibrillation, stroke, dementia, and premature death.

Background Interatrial block (IAB) has been associated with supraventricular arrhythmias and stroke, and even with sudden cardiac death in the general population. Whether IAB is associated with life‐threatening arrhythmias (LTA) and sudden cardiac death in dilated cardiomyopathy (DCM) remains unknown. This study aimed to determine the association between IAB and LTA in ambulant patients with DCM. Methods and Results A derivation cohort (Maastricht Dilated Cardiomyopathy Registry; N=469) and an external validation cohort (Utrecht Cardiomyopathy Cohort; N=321) were used for this study. The presence of IAB (P‐wave duration>120 milliseconds) or atrial fibrillation (AF) was determined using digital calipers by physicians blinded to the study data. In the derivation cohort, IAB and AF were present in 291 (62%) and 70 (15%) patients with DCM, respectively. LTA (defined as sudden cardiac death, justified shock from implantable cardioverter‐defibrillator or anti‐tachypacing, or hemodynamic unstable ventricular fibrillation/tachycardia) occurred in 49 patients (3 with no IAB, 35 with IAB, and 11 patients with AF, respectively; median follow‐up, 4.4 years [2.1; 7.4]). The LTA‐free survival distribution significantly differed between IAB or AF versus no IAB (both P

El síndrome de Bayés es una entidad clínica que se define como la asociación entre la presencia de bloqueo interauricular avanzado (BIA-A), y el desarrollo de taquiarritmias supraventriculares (TSV), siendo la fibrilación auricular (FA), la más frecuente. Esta asociación salió a la luz con los estudios del Prof. Antoni Bayés de Luna en los años ‘80. Estudios realizados posteriormente por otros grupos encontraron una fuerte asociación entre este síndrome y la ocurrencia de fenómenos tromboembólicos, siendo el accidente cerebrovascular (ACV) el más grave. Del mismo modo, se documentó una asociación con deterioro cognitivo y demencia. Esto generó la pregunta acerca de si la terapia de anticoagulación previa a la documentación de FA podría prevenir la ocurrencia de tromboembolismos asociados al BIA-A y de esta manera preservar el estado cognitivo. Esta pregunta permanece, aún hoy, sin respuesta definitiva. Existen estudios en diferentes estadios de su desarrollo cuyo objetivo es comparar la efectividad de la anticoagulación en pacientes con BIA-A y sin FA documentada. Los resultados de los mismos permitirán establecer la efectividad de esta opción terapéutica temprana y, de manera conclusiva, definir si, para decidir anticoagular un paciente, la FA tiene que ser previamente documentada o no.

In the Cardiology Masters section of European Cardiology Review, we bring you an insight into the career of a key contributor to the field of cardiology. In this issue, we feature Professor Antonio Bayés de Luna, Senior Researcher at the Cardiovascular Research Foundation, Cardiovascular ICCC-Program, Research Institute, Hospital de Sant Pau, IIB Sant Pau, Barcelona, Spain.

Background The clinical significance of conduction disturbances after transcatheter aortic valve implantation has been described; however, little is known about the influence of baseline ECGs in the prognosis of these patients. Our aim was to study the influence of baseline ECG parameters, including interatrial block (IAB), in the prognosis of patients treated with transcatheter aortic valve implantation. Methods and Results The BIT (Baseline Interatrial Block and Transcatheter Aortic Valve Implantation) registry included 2527 patients with aortic stenosis treated with transcatheter aortic valve implantation. A centralized analysis of baseline ECGs was performed. Patients were divided into 4 groups: normal P wave duration (

Abstract Background To evaluate the possibility of left atrial (LA) remodeling using speckle tracking echocardiography (STE) in patients with interatrial block (IAB). Methods We performed a cross-sectional study with three groups of patients: 56 without IAB, 21 with partial IAB (pIAB), and 22 with advanced IAB (aIAB). Transthoracic echocardiographic (TTE) STE was performed and clinical and echocardiographic findings were analyzed. Results TTE showed higher LA volume/body surface area in the patients with IAB. With STE, the absolute value of strain rate during atrial booster pump function (SRa) and early reservoir period (SRs) decreased in the pIAB group and even more in the aIAB group, compared to the group without IAB. The independent variables were the echocardiographic measures of LA size and function. After adjusting for confounders, both multiple linear regression and multivariate multinomial regression showed good correlation with dependent variables: longer P-wave duration on electrocardiography and with the type of IAB, respectively. SRa (p

Abstract Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with stroke, cognitive impairment, and cardiovascular death. Some predisposing factors − as aging, diabetes, hypertension − induce and maintain electrophysiological and ultrastructural remodeling that usually includes fibrosis. Interatrial conduction disturbances play a crucial role in the initiation of atrial fibrosis and in its associated complications. The diagnosis of interatrial blocks (IABs) is easy to perform using the surface ECG. IAB is classified as partial when the P wave duration is ≥120 ms, and advanced if the P wave also presents a biphasic pattern in II, III and aVF. IAB is very frequent in the elderly and, particularly in the case of the advanced type, is associated with AF, AF recurrences, stroke, and dementia. The anticoagulation in elderly patients at high risk of AF without documented arrhythmias is an open issue but recent data suggest that it might have a role, particularly in elderly patients with structural heart disease, high CHA2DS2VASc (Congestive heart failure/left ventricular dysfunction, Hypertension, Age ≥ 75 [doubled], Diabetes, Stroke [doubled] – Vascular disease, Age 65–74, and Sex category [female]), and advanced IAB. In this debate, we discuss the association of surface ECG IAB, a marker of atrial fibrosis, with AF and stroke. We also present the rationale that justifies further studies regarding anticoagulation in some of these patients.

Background Patients with chronic heart failure are at high risk of sudden cardiac death (SCD). Increased dispersion of repolarization restitution has been associated with SCD, and we hypothesize that this should be reflected in the morphology of the T‐wave and its variations with heart rate. The aim of this study is to propose an electrocardiogram (ECG)‐based index characterizing T‐wave morphology restitution (TMR), and to assess its association with SCD risk in a population of chronic heart failure patients. Methods and Results Holter ECGs from 651 ambulatory patients with chronic heart failure from the MUSIC (MUerte Súbita en Insuficiencia Cardiaca) study were available for the analysis. TMR was quantified by measuring the morphological variation of the T‐wave per RR increment using time‐warping metrics, and its predictive power was compared to that of clinical variables such as the left ventricular ejection fraction and other ECG‐derived indices, such as T‐wave alternans and heart rate variability. TMR was significantly higher in SCD victims than in the rest of patients (median 0.046 versus 0.039, P

Sudden cardiac death (SCD) and pump failure death (PFD) are common endpoints in chronic heart failure (CHF) patients, but prevention strategies are different. Currently used tools to specifically predict these endpoints are limited. We developed risk models to specifically assess SCD and PFD risk in CHF by combining ECG markers and clinical variables.The relation of clinical and ECG markers with SCD and PFD risk was assessed in 597 patients enrolled in the MUSIC (MUerte Súbita en Insuficiencia Cardiaca) study. ECG indices included: turbulence slope (TS), reflecting autonomic dysfunction; T-wave alternans (TWA), reflecting ventricular repolarization instability; and T-peak-to-end restitution (ΔαTpe) and T-wave morphology restitution (TMR), both reflecting changes in dispersion of repolarization due to heart rate changes. Standard clinical indices were also included.The indices with the greatest SCD prognostic impact were gender, New York Heart Association (NYHA) class, left ventricular ejection fraction, TWA, ΔαTpe and TMR. For PFD, the indices were diabetes, NYHA class, ΔαTpe and TS. Using a model with only clinical variables, the hazard ratios (HRs) for SCD and PFD for patients in the high-risk group (fifth quintile of risk score) with respect to patients in the low-risk group (first and second quintiles of risk score) were both greater than 4. HRs for SCD and PFD increased to 9 and 11 when using a model including only ECG markers, and to 14 and 13, when combining clinical and ECG markers.The inclusion of ECG markers capturing complementary pro-arrhythmic and pump failure mechanisms into risk models based only on standard clinical variables substantially improves prediction of SCD and PFD in CHF patients.