3D printing in anatomical lung segmentectomies: A randomized pilot trial.

Objective: This pilot study evaluated the impact of using a 3D printed model of the patient's bronchovascular lung anatomy on the mental workload and fatigue of surgeons during full thoracoscopic segmentectomy. Design: We performed a feasibility pilot study of a prospective randomized controlled trial with 2 parallel arms. All included patients underwent digital 3D visual reconstruction of their bronchovascular anatomy and were randomized into the following two groups: Digital arm (only a virtual 3D model was available) and Digital + Object arm (both virtual and printed 3D models were available). The primary end-point was the surgeons' mental workload measured using the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) score. Setting: Between October 28, 2020 and October 05, 2021, we successively investigated all anatomic segmentectomies performed via thoracoscopy in the Thoracic Department of the Montsouris Mutualiste Institute, except for S6 segmentectomies and S4+5 left bi-segmentectomies. Participants: We assessed 102 patients for anatomical segmentectomy. Among the, 40 were randomly assigned, and 34 were deemed analysable, with 17 patients included in each arm. Results: Comparison of the two groups, each comprising 17 patients, revealed no statistically significant difference in primary or secondary end-points. The consultation of the visual digital model was significantly less frequent when a 3D printed model was available (6 versus 54 consultations, p = 0.001). Notably, both arms exhibited high NASA-TLX scores, particularly in terms of mental demand, temporal demand, and effort scores. Conclusion: In our pilot study, 3D printed models and digital 3D reconstructions for pre-operative planning had an equivalent effect on thoracoscopic anatomic segmentectomy for experienced surgeons. The originality of this study lies in its focus on the impact of 3D printing of bronchovascular anatomy on surgeons, rather than solely on the surgical procedure.

Sudden cardiac arrest: ECG repolarization after resuscitation.

INTRODUCTION: Early repolarization (ERep) abnormalities on electrocardiogram (ECG) are common immediately following cardiac arrest. We characterized and correlated electrocardiographic repolarization abnormalities immediately after cardiac arrest with acute coronary angiography. METHODS AND RESULTS: We studied 225 consecutive patients presenting with out-of-hospital cardiac arrest. All these patients had successful cardiopulmonary resuscitation and acute coronary angiography. The first ECG recorded after successful resuscitation was analyzed by two independent cardiologists. Patients were categorized according to their repolarization pattern. Pattern 1: No ST segment elevation or ERep. Pattern 2: ST segment elevation without ERep. Pattern 3: ST segment elevation and ERep. Pattern 4: ERep only. Patterns 1, 2, 3, and 4 were found in 112 (50%), 74 (33%), 19 (8%), and 20 (9%) patients, respectively. Cardiac arrest was due to acute myocardial ischemia in 45%, 82%, 39%, and 15% of patients in groups 1, 2, 3 and 4, respectively (P < 0.0001). Sensitivity and specificity of pattern 2 was 50% and 88%, respectively, for acute coronary lesion, whereas isolated ERep pattern occurred in 9% of cases and was associated with a nonischemic event (80%). Among 65 patients (29%) who survived, 7% of patients with pattern 1, 13% with pattern 2, 60% with pattern 3, and 88% with pattern 4 exhibited ERep on ECG during the follow-up. CONCLUSION: In the context of cardiac resuscitation, an ECG with ST elevation favors acute myocardial infarction, whereas the presence of ERep is a marker of a nonischemic event and future ERep syndrome.

Single-catheter simplified stepwise approach to persistent atrial fibrillation ablation: A feasibility study.

BACKGROUND: The strategy for atrial fibrillation ablation in persistent atrial fibrillation remains controversial. A single-catheter approach was recently validated for pulmonary vein isolation. AIM: To evaluate the feasibility of this approach to performing persistent atrial fibrillation ablation, including pulmonary vein isolation and atrial lines, if needed. METHODS: We prospectively included 159 consecutive patients referred to our centre for a first persistent atrial fibrillation ablation between January 2018 and December 2018. All patients underwent pulmonary vein isolation. If the patient was still in atrial fibrillation (spontaneously or inducible), we subsequently performed a stepwise approach, including roof line, anterior mitral line, posterior box lesion and cavotricuspid isthmus line. Finally, if patient remained in atrial fibrillation at the end of the procedure, a synchronized direct-current cardioversion was applied to restore sinus rhythm. RESULTS: At baseline, 54 patients were in sinus rhythm and underwent pulmonary vein isolation. For patients in atrial fibrillation, after pulmonary vein isolation and ablation of additional lines, if needed, 18 patients were converted to atrial tachycardia and one directly to sinus rhythm; 96 were still in atrial fibrillation and underwent direct-current cardioversion. After a mean follow-up of 17±6 months, 57 patients (36%) experienced atrial arrhythmia recurrence. No deaths, tamponades or phrenic nerve injuries were observed following the procedure. The main mode of arrhythmia recurrence was atrial fibrillation in 75% of cases and atrial tachycardia in 25% of cases. CONCLUSION: A single-catheter approach, including pulmonary vein isolation and atrial lines, is feasible and safe in patients undergoing persistent atrial fibrillation ablation, with an acceptable success rate of 64% at mid-term follow-up.

Definition of success criteria for ablation of typical right atrial flutter with a single-catheter approach: A pilot study.

BACKGROUND: The success rate of cavotricuspid isthmus ablation to treat right common flutter is high (up to 95%), but needs bidirectional block confirmation, requiring two or three catheters. AIM: To describe a new pacing technique using a single catheter to ablate and confirm cavotricuspid isthmus block with differential PR interval measurements. METHODS: We included 61 patients from five centres, who were referred for cavotricuspid isthmus ablation. All patients had cavotricuspid isthmus ablation, and the cavotricuspid isthmus block was confirmed by differential pacing using two or three catheters. The new method consisted of measuring the PR interval on the surface electrocardiogram using pacing from the tip of the ablation catheter on the lateral side (lateral delay) and the septal side (coronary sinus ostium) of the cavotricuspid isthmus line (difference=delta PR interval), before and after cavotricuspid isthmus ablation. We analysed the value of the delta PR interval in predicting bidirectional cavotricuspid isthmus block as confirmed by standard methods. RESULTS: Among our patient population (mean age 63±12 years), 39 patients were ablated during sinus rhythm, and 22 during common flutter. Cavotricuspid isthmus block was achieved in all patients but one. Lateral delay and delta PR interval increased significantly after validation of cavotricuspid isthmus block (257±42 vs. 318±50ms and 32±23 vs. 96±22ms, respectively; P<0.0001). A delta PR interval cut-off of ≥70ms had 100% sensitivity and specificity to predict bidirectional cavotricuspid isthmus block. CONCLUSIONS: A single-catheter ablation approach to performing cavotricuspid isthmus line based on surface electrocardiogram PR interval measurement is feasible. After ablation, cavotricuspid isthmus block was systematically obtained when the delta PR interval was>70ms.