Anatomic predictors of recurrence after cryoablation for atrial fibrillation: a computed tomography based composite score.

BACKGROUND: Effective pulmonary vein isolation (PVI) with cryoablation depends on adequate occlusion of pulmonary veins (PV) by the cryoballoon and is therefore likely to be affected by PV and left atrial (LA) anatomical characteristics and variants. Thus, the objective of this study was to investigate the effect of LA and PV anatomy, evaluated by computed tomography (CT), on acute and long-term outcomes of cryoablation for atrial fibrillation (AF). METHODS: Fifty-eight patients (64.72 + 9.44 years, 60.3% male) undergoing cryoablation for paroxysmal or early persistent AF were included. Pre-procedural CT images were analyzed to evaluate LA dimensions and PV anatomical characteristics. Predictors of recurrence were identified using regression analysis. RESULTS: 60.3% of patients had two PVs on each side with separate ostia, whereas 29.3% and 10.3% had right middle and left common PVs, respectively. The following anatomic characteristics were found to be independent predictors of recurrence: right superior PV ostial max:min diameter ratio > 1.32, left superior PV ostial max:min diameter ratio > 1.2, right superior PV antral circumference > 69.1 mm, right inferior PV antral circumference > 61.38 mm, right superior PV angle > 22.7°. Using these factors, LA diameter and right middle PV, a scoring model was created for prediction of "unfavorable" LA-PV anatomy (AUC = 0.867, p = 0.000009, score range = 0-7). Score of ≥ 4 predicted need for longer cryoenergy ablation (p = 0.039) and more frequent switch to radiofrequency energy (p = 0.066) to achieve PVI, and had a sensitivity of 83.3% and specificity of 82.5% to predict clinical recurrence. CONCLUSION: CT-based scoring system is useful to identify "unfavorable" anatomy prior to cryo-PVI, which can result in procedural difficulty and poor outcomes.

Evaluation of acute chest pain: Evolving paradigm of coronary risk scores and imaging.

There is a broad differential diagnosis for patients presenting with acute chest pain. History, physical examination, electrocardiogram, and serial troponin assays are pivotal in assessing patients with suspected acute coronary syndrome. However, if the initial workup is equivocal, physicians are faced with a challenge to find the optimal strategy for further triage. Risk stratification scores have been validated for patients with known acute coronary syndrome, such as the TIMI and GRACE scores, but there may be limitations in undifferentiated chest pain patients. Advancements in imaging modalities such as coronary computed tomography angiography and the addition CT derived fractional flow reserve, have demonstrated utility in evaluating patients presenting with acute chest pain. With this article, we aim to provide a comprehensive review of the non-invasive modalities that are available to evaluate acute chest pain patients suspected of cardiac etiology in the emergency room. We also added a focus on new imaging modalities that have shown to have prognostic implications in stable ischemic heart disease.

A standardized protocol to reliably visualize the left atrial appendage with intracardiac echocardiography: Importance of multiple imaging sites.

BACKGROUND: Currently, there is no accepted protocol for left atrial appendage (LAA) imaging with intracardiac echocardiography (ICE). OBJECTIVE: This study aimed to assess the utility of ICE to reliably visualize the entire cavity of the LAA and propose a specific procedural protocol to achieve the above objective. METHODS: We created a three-dimensional reconstruction of the LAA, using two-dimensional ICE sections obtained from three different location (the right atrium [RA], right ventricle inflow [RVI], and right ventricular outflow [RVOT]). We then compared the three-dimensional LAA reconstruction by ICE with one obtained by cardiac computed tomography angiography (CCTA) for morphological and volume differences. RESULTS: Three-dimensional reconstruction with ICE could reliably reproduce the LAA as visualized with CCTA but only when ICE sampling was performed from at least two catheter positions. There was no statistically significant difference between LAA volumes obtained with ICE and CCTA (P = 0.33). The contribution of each anatomical location to the total volume was 17% ± 16.6%, 74% ± 13.3%, and 33% ± 26% for RA, RVI, and RVOT, respectively. CONCLUSION: In comparison with CCTA, the LAA can be reliably visualized in its entity by ICE, but only if multiple imaging positions (RA, RV inflow, and RVOT) are used.

The neglected lead on electrocardiogram: T wave inversion in lead aVL, nonspecific finding or a sign for left anterior descending artery lesion?

BACKGROUND: The electrocardiogram (ECG) is the most important diagnostic tool for acute myocardial infarction (AMI). T wave inversion (TWI) in lead aVL has not been emphasized or well recognized. OBJECTIVE: This study examined the relationship between the presence of TWI before the event and mid-segment left anterior descending (MLAD) artery lesion in patients with AMI. METHODS: Retrospective charts of patients with acute coronary syndrome between the months of January 2009 and December 2011 were reviewed. All patients with MLAD lesion were identified and their ECG reviewed for TWI in lead aVL. RESULTS: Coronary angiography was done on 431 patients. Of these, 125 (29%) had an MLAD lesion. One hundred and six patients (84.8%) had a lesion > 50% and 19 patients (15.2%) had a lesion < 50%. Of the 106 patients who had a MLAD lesion > 50%, 90 patients (84.9%) had TWI in lead aVL and one additional lead. Of the 19 patients who had an MLAD lesion < 50%, 8 patients (42.1%) had TWI in lead aVL and one additional lead. Isolated TWI in lead aVL had an overall sensitivity of 76.7% (95% confidence interval [CI] 0.65-0.86), a specificity of 71.4% (95% CI 0.45-0.88), a positive predictive value of 92%, a negative predictive value of 41.7%, a positive likelihood ratio of 2.7 (95% CI 1.16-6.22), and negative likelihood ratio of 0.32 (95% CI 0.19-0.58) for predicting a MLAD lesion of > 50% (p = 0.0011). CONCLUSIONS: TWI in lead aVL might signify a mid-segment LAD lesion. Recognition of this finding and early appropriate referral to a cardiologist might be beneficial. Additional studies are needed to validate this finding.