[Development of a Novel Simple Electrophysiological Study During Atrial Fibrillation Surgery:the Methods of Identifying AFs Where Pulmonary Vein Isolation is Effective].

BACKGROUND & AIM: Surgical procedure for chronic atrial tiburillation (Af) associated with organic cardiac disease is still superior, but atrial potential mapping has rarely been performed for these patients. An epicardial mapping is necessary to elucidate the electrophysiology of Af as a disease, and to verify whether interventions are correctly performed to establish surgical treatment. We report the development of a new method that enables simple and immediate intraoperative decisions electrophysiologically. METHODS & RESULTS: To realize real-time epi-atrial mapping, we planned to apply the mapping system (ExTRa Mapping System), which is already clinically applied during catheter ablation in Japan, for potential acquisition analysis. We developed an epicardial probe (20-point spiral electrode, 25 mm in diameter) that is compatible with the ExTRa mapping system. Using these electrodes, 5-second continuous recordings were made at 12 right atrial (RA) and 7 left atrial (LA) areas, covering the entire atrial surface, to confirm the existence and distribution of multiple wavelets and their central rotors (Ro). Both atria were mapped in 3 patients with chronic Af with mitral valve disease who underwent open heart surgery through a median sternotomy (mean age 73 years, 3 males). Ro was clearly expressed on the monitor display which can be observed by operator in real time. DISCUSSION & CONCLUSION: The system we have developed made it possible to observe Ro, which electrically characterize chronic Af, including their distribution in real time. The development of electrophysiologically- supported theoretical Af surgery can be expected through the accumulation of cases, detailed potential analysis, and verification of the placement of the isolation line and surgical results.

Distal Stent Graft-Induced New Entry After Frozen Elephant Trunk Procedure for Aortic Dissection.

BACKGROUND: The purpose of this study was to evaluate the risk factors of distal stent graft-induced new entry (dSINE) after frozen elephant trunk (FET) procedure for aortic dissection (AD) and to consider strategies to prevent this complication. METHODS: This retrospective review included 52 patients who had undergone aortic arch repair for AD with the FET procedure using J Graft FROZENIX from 2014 to 2020 at a single center. Baseline characteristics, aortic characteristics and mid-term outcomes were compared between patients with and without dSINE. The extent of unfolding of the device and movement of the distal edge of the device were analyzed by multidetector computed tomography. The primary endpoints were survival and freedom from reintervention. RESULTS: dSINE was the most prevalent complication after FET procedure, with an incidence of 23%. Eleven of 12 patients with dSINE underwent secondary interventions. dSINE was common in chronic aortic dissection (P = 0.001) and was associated with the residual false lumen area (P < 0.001) and movement distance of the distal edge of the device in the cranial direction (P < 0.001). CONCLUSIONS: The distal edge of the FET is more likely to move in the cranial direction, and this movement may cause dSINE.

Influence of Type 2 Endoleaks on Long-Term Outcomes after Endovascular Repair for Abdominal Aortic Aneurysms: A National Hospital Organization Network Study for Abdominal Aortic Aneurysms in Japan.

BACKGROUND: Although endovascular repair (EVAR) is the first-line treatment for abdominal aortic aneurysm, type 2 endoleak (EL), which is associated with late sac enlargement or rupture, remains a concern. The present study aimed to assess the influence of type 2 EL on long-term outcomes after EVAR. METHODS: Among 550 patients who underwent EVAR between 2007 and 2013 at 14 Japanese national hospitals, 135 patients had type 2 EL diagnosed on follow-up computed tomography (CT) within 12 months after EVAR (EL2[+] group) and 415 patients did not have EL within 12 months (EL2[-] group). The cumulative incidences of sac enlargement, late intervention, and aneurysm-related death after EVAR were estimated using the cumulative incidence function method, and prognostic factors were investigated using the Fine-Gray hazard model. RESULTS: The median follow-up period was 5 years, and the 5-year cumulative incidence rates of sac enlargement, late intervention, and aneurysm-related death were 30.7% ± 4.4%, 25.3% ± 4.1%, and 2.6% ± 1.4%, respectively, in the EL2(+) group, and 8.7% ± 1.6%, 7.6% ± 1.4%, and 0.3% ± 0.3%, respectively, in the EL2(-) group. The cumulative incidence rates of sac enlargement (P = 0.002), late intervention (P < 0.001), and aneurysm-related death (P = 0.015) were significantly different between the 2 groups. As the first-line treatment for sac enlargement with type 2 EL, transcatheter coil embolization was performed in 30 patients. Information about sac behavior on CT after coil embolization was available in 20 of the 30 patients. Among these patients, no patients experienced sac shrinkage, and the aneurysmal sac dilated after coil embolization in 18 patients. CONCLUSIONS: Type 2 EL affects the long-term outcomes after EVAR. It is not recommended to observe large aneurysmal sacs conservatively as they tend to dilate in the presence of type 2 EL.

H558R, a common SCN5A polymorphism, modifies the clinical phenotype of Brugada syndrome by modulating DNA methylation of SCN5A promoters.

BACKGROUND: A common SCN5A polymorphism H558R (c.1673 A > G, rs1805124) improves sodium channel activity in mutated channels and known to be a genetic modifier of Brugada syndrome patients (BrS). We investigated clinical manifestations and underlying mechanisms of H558R in BrS. METHODS AND RESULTS: We genotyped H558R in 100 BrS (mean age 45 ± 14 years; 91 men) and 1875 controls (mean age 54 ± 18 years; 1546 men). We compared clinical parameters in BrS with and without H558R (H558R+ vs. H558R- group, N = 9 vs. 91). We also obtained right atrial sections from 30 patients during aortic aneurysm operations and compared SCN5A expression and methylation with or without H558R. H558R was less frequent in BrS than controls (9.0% vs. 19.2%, P = 0.028). The VF occurrence ratio was significantly lower (0% vs. 29.7%, P = 0.03) and spontaneous type 1 ECG was less observed in H558R+ than H558R- group (33.3% vs. 74.7%, P = 0.01). The SCN5A expression level was significantly higher and the methylation rate was significantly lower in sections with H558R (N = 10) than those without (0.98 ± 0.14 vs. 0.83 ± 0.19, P = 0.04; 0.7 ± 0.2% vs. 1.6 ± 0.1%, P = 0.004, respectively). In BrS with heterozygous H558R, the A allele mRNA expression was 1.38 fold higher than G allele expression. CONCLUSION: The SCN5A polymorphism H558R may be a modifier that protects against VF occurrence in BrS. The H558R decreased the SCN5A promoter methylation and increased the expression level in cardiac tissue. An allelic expression imbalance in BrS with a heterozygous H558R may also contribute to the protective effects in heterozygous mutations.

Preoperative Tissue Doppler Imaging-Derived Atrial Conduction Time Predicts Postoperative Atrial Fibrillation in Patients Undergoing Mitral Valve Surgery for Mitral Valve Regurgitation.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery and may result in stroke, heart failure and poor prognosis. This study evaluated a novel index of total atrial conduction time derived from the P-wave onset (lead II) to the peak A' wave on tissue Doppler imaging (PA-TDI duration) in patients undergoing mitral valve surgery (MVS) for mitral valve regurgitation. METHODS AND RESULTS: Seventy-three patients undergoing MVS had transthoracic echocardiography with tissue Doppler imaging preoperatively and were monitored postoperatively with continuous electrocardiographic telemetry for 14 days. Preoperative characteristics, echocardiographic data, operative data and postoperative findings were compared between patients with (n=44) and without (n=29) POAF. Postoperative cardiac events were higher in patients with than without POAF (12/44, 27% vs. 3/29, 10%; P=0.0798) and cerebral events occurred in only 2 POAF patients. On multivariate analysis the independent predictors of POAF were degenerative disease etiology (OR, 4.61; 95% CI: 1.41-15.0; P=0.0112) and PA-TDI duration (OR, 1.04; 95% CI: 1.01-1.07; P=0.0048). On ROC curve analysis a PA-TDI cut-off of 159.4 ms was optimal for predicting POAF. CONCLUSIONS: PA-TDI duration was an independent predictor of POAF after MVS. Patients with PA-TDI duration >159.4 ms should be considered high risk and treated appropriately to improve outcome.

Efficacy of cardiopulmonary rehabilitation with adaptive servo-ventilation in patients undergoing off-pump coronary artery bypass grafting.

BACKGROUND: Postoperative complications after cardiac surgery increase mortality. This study aimed to evaluate the efficacy of cardiopulmonary rehabilitation with adaptive servo-ventilation (ASV) in patients undergoing off-pump coronary artery bypass grafting (OPCAB). METHODS AND RESULTS: A total of 66 patients undergoing OPCAB were enrolled and divided into 2 groups according to the use of ASV (ASV group, 30 patients; non-ASV group, 36 patients). During the perioperative period, all patients undertook cardiopulmonary rehabilitation. ASV was used from postoperative day (POD) 1 to POD5. Hemodynamics showed a different pattern in the 2 groups. Blood pressure (BP) on POD6 in the ASV group was significantly lower than that in the non-ASV group (systolic BP, 112.9±12.6 vs. 126.2±15.8 mmHg, P=0.0006; diastolic BP, 62.3±9.1 vs. 67.6±9.3 mmHg, P=0.0277). The incidence of postoperative atrial fibrillation (POAF) was lower in the ASV group than in the non-ASV group (10% vs. 33%, P=0.0377). The duration of oxygen inhalation in the ASV group was significantly shorter than that in the non-ASV group (5.1±2.2 vs. 7.6±6.0 days, P=0.0238). The duration of postoperative hospitalization was significantly shorter in the ASV group than in the non-ASV group (23.5±6.6 vs. 29.0±13.1 days, P=0.0392). CONCLUSIONS: Cardiopulmonary rehabilitation with ASV after OPCAB reduces both POAF occurrence and the duration of hospitalization.

Effects of the topographical extent of coronary artery ectasia on coronary blood flow in patients with aortic aneurysms.

Aortic aneurysms are associated with coronary artery ectasia (CAE). However, the relation between the extent of CAE and coronary blood flow in patients with aortic aneurysms is not fully understood. This study was undertaken to assess the angiographic characteristics and effects of the topographical extent of CAE on coronary blood flow in patients with aortic aneurysms. This study consisted of 93 consecutive patients with aortic aneurysms (AA group) and 79 patients without aortic aneurysms who had angiographically normal coronary arteries as the control group (Control group). Coronary flow velocity was determined using the thrombolysis in myocardial infarction frame count (TFC) and the topographical extent of CAE was assessed. In the AA group, 43 patients (46.2 %) had significant coronary artery stenosis and 37 patients (40.2 %) had diffuse CAE. TFC was significantly higher in the AA group than in the control group in all 3 coronary arteries. Furthermore, mean corrected TFC (CTFC) was significantly higher in the AA group than in the control group (40.1 ± 10.7 vs. 25.8 ± 6.5, p < 0.001). In the AA group, mean CTFC in patients with diffuse CAE was significantly higher than that in patients with segmental CAE (50.2 ± 8.7 vs. 33.6 ± 5.2, p < 0.001). The mean CTFC correlated positively with the topographical extent of CAE. Many patients with aortic aneurysms were accompanied with angiographic coronary artery stenosis and CAE. Furthermore, patients with aortic aneurysms had higher CTFC than those without aortic aneurysms and it was primarily driven by more frequent prevalence of diffuse CAE.

Trehalose protects against spinal cord ischemia in rabbits.

OBJECTIVE: This study tested to see if trehalose, a cytoprotective disaccharide, protects against spinal cord ischemia in a rabbit model. METHODS: The infrarenal aorta was mobilized in four groups of 10 rabbits. In groups I, II, and III, it was clamped proximally and distally for 20 minutes. In group I, the clamped aorta was infused at 2.5 L/min for 2 hours with lactated Ringer's (LR) solution. In group II, the clamped aorta was infused with 5% trehalose in LR. LR was administered intravenously (2.0 mL/min) in groups I and II starting 30 minutes before clamping. In group III, 5% trehalose in LR was infused intravenously only. Group IV was a sham-operated control group without aortic clamping. At 8, 24, and 48 hours after reperfusion, hind limb function was scored using the Tarlov score (paralysis = 0, perceptible joint movement = 1, good joint movement but unable to stand = 2, able to walk = 3, normal = 4). Histologic analysis and electron microscopy were performed on anterior horn cells. RESULTS: The Tarlov scores in groups I, II, and III were, respectively, 1.1 ± 1.4, 3.5 ± 0.5, and 2.9 ± 0.9 at 8 hours; 0.8 ± 1.2, 3.9 ± 0.3, and 2.9 ± 0.9 at 24 hours; and 0.6 ± 0.7, 3.9 ± 0.3, and 2.7 ± 0.9 at 48 hours after reperfusion. Group IV scores were normal (4 ± 0) at all assessments. These scores were higher in groups II and III than in group I (P < .01) at all assessments. Scores at 24 and 48 hours were higher in group II than in group III (P < .05). In group III, delayed paraparesis developed in one rabbit at 24 hours and in two more at 48 hours. Histopathologic analysis showed the number of normal neurons was higher in groups II (P < .0001), III (P = .006), and IV (P < .0001) vs group I. Electron microscopy confirmed preserved neuronal cell ultrastructure in rabbits with normal limb function. CONCLUSIONS: Transaortic trehalose infusion was protective against paraplegia, whereas intravenous trehalose reduced spinal cord ischemia. This study was preliminary and further studies are needed.

Preoperative tissue Doppler imaging-derived atrial conduction time can predict postoperative atrial fibrillation in patients undergoing aortic valve replacement for aortic valve stenosis.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery and may result in stroke or heart failure and poor prognosis. This study aimed to evaluate a novel index of total atrial conduction time derived from the P-wave onset (lead II) to the peak A' wave on tissue Doppler imaging (PA-TDI duration). The PA-TDI duration was compared with previously reported predictors of POAF, and the optimal cutoff value of PA-DTI was calculated in patients undergoing aortic valve replacement (AVR) for AV stenosis (AS). METHODS AND RESULTS: We enrolled 63 patients undergoing isolated AVR. They underwent transthoracic echocardiography with TDI preoperatively and were monitored postoperatively with continuous electrocardiographic telemetry for 7 days. The hospital stay was significantly longer in the 41 patients with POAF than in the 22 without POAF (33.8±19.7 vs. 24.1±8.1 days, P=0.03). Multivariate analysis revealed that PA-TDI duration (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.02-1.13; P=0.0072) and age (OR, 1.14; CI, 1.03-1.28; P=0.016) were significant independent predictors of POAF. Receiver-operating characteristic curve analysis showed the optimal cutoff values of PA-TDI duration and age were 147.3 ms and 74 years, respectively. CONCLUSIONS: The PA-TDI duration was an independent predictor of POAF after AVR for AS. Patients with PA-TDI duration >147 ms should be considered high risk and treated appropriately to improve outcomes.

Prediction of atrial fibrillation after off-pump coronary artery bypass grafting using preoperative total atrial conduction time determined on tissue Doppler imaging.

BACKGROUND: Postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery and results in increased health-care utilization. This study identified new transthoracic echocardiographic predictors of POAF using an index of the total atrial conduction time derived on tissue Doppler imaging (PA-TDI duration) in patients undergoing off-pump coronary artery bypass grafting (OPCAB). METHODS AND RESULTS: A total of 88 patients undergoing isolated OPCAB were enrolled. They were examined preoperatively on transthoracic echocardiography with tissue Doppler evaluations and monitored postoperatively with continuous electrocardiographic telemetry for 7 days. POAF occurred in 35 patients (39.8%). Patients with POAF had a significantly longer duration of hospital stay than those without (44.9±6.2 vs. 37.3±3.3 days, P=0.04). Multivariate analysis showed that PA-TDI duration (odds ratio [OR], 1.11; 95% confidence interval [CI]: 1.06-1.16; P=0.0001) and left atrial volume index (LAVI; OR, 1.11; 95% CI: 1.02-1.20; P=0.01) were independent predictors of POAF. Moreover, PA-TDI duration was more reliable, given an area under the receiver operating characteristic curve of 0.85 (sensitivity, 74.3%; specificity, 86.8%). CONCLUSIONS: PA-TDI duration was an independent predictor of POAF following OPCAB. Awareness of risk of POAF may lead to the prevention of POAF, a rapid response to POAF, shortened hospital stay, and improved prognosis.

Transintercostal-evoked spinal cord potential in thoracic aortic surgery.

BACKGROUND: We have developed a novel method of measuring spinal cord-evoked potentials with stimulation and recording at the intercostal nerves (transintercostal-evoked spinal cord potential: Tic-ESCP). The purpose of this study was to examine the feasibility and accuracy of Tic-ESCP during thoracic aortic surgery. METHODS: In addition to the conventional electrodes (cranial and intrathecal), stimulating and recording electrodes were placed on the intercostal nerves that were located at a cephalad and caudal level relative to the aneurysm after the pleura on the intercostal nerves was opened. Specially designed hook-type electrodes were anchored to the nerves and surroundings atraumatically and fixed on the pleura. The conventional transcranial motor-evoked potential (Tc-MEP) and Tic-ESCP were recorded simultaneously. Eight patients were examined in this study. RESULTS: In all patients, Tic-ESCP could be clearly recorded with biphasic waveforms consisting of first a positive wave and a subsequent negative wave. In all 8 patients, the waveform of Tc-MEP and Tic-ESCP changed during aortic reconstruction. In 2 cases, the waveform of Tc-MEP and Tic-ESCP decreased below 50% of baseline during aortic clamping and the intercostal arteries were reconstructed with no resultant spinal cord injury. In 1 case with a shaggy aorta, Tc-MEP and Tic-ESCP had different values and each evoked potential could have reflected that regional spinal cord infarction and paraplegia had occurred. CONCLUSIONS: Tic-ESCP was clinically feasible and changes were compatible with the conventional Tc-MEP. The Tic-ESCP waveforms were simple and appeared to be specific to the spinal cord within the target range, in contrast to the other evoked potentials which are multimorphic and reflect the amplitudes at the brain and multiple levels of the spinal cord.

Transaortic stent grafting of a Kommerell diverticulum arising from a right-sided aortic arch.

In this article, we report the case of a 68-year-old woman who presented with shortness of breath. Respiratory function tests showed a slightly obstructive physiology. Computed tomography (CT) results revealed an aberrant left subclavian artery and a Kommerell diverticulum arising from a right-sided aortic arch that was compressing the trachea and the surrounding tissues. A median sternotomy was performed with the patient under circulatory arrest with moderate hypothermia, and a transaortic stent graft was inserted to exclude the Kommerell diverticulum. The aberrant left subclavian artery was ligated and an axillo-axillar bypass was constructed. Postoperative CT showed complete exclusion of the Kommerell diverticulum without an endoleak. The patient's breathing difficulty was resolved, and she was discharged uneventfully. This procedure should be considered as an alternative strategy for exclusion of Kommerell diverticulum.

Modified septal myectomy using a curved knife for left ventricular septal hypertrophy.

An 86-year-old woman presented with chest pain and discomfort. Echocardiography revealed severe aortic valve stenosis and asymmetric septal hypertrophy. Aortic valve replacement and myectomy were performed using a curved knife. The blade was U-shaped in cross-section, and was curved upward along the long axis. Hypertrophic septal myocardium was removed along the long axis of the left ventricle (LV), and a groove for blood flow was constructed. The patient was discharged uneventfully without recurrence of her chest discomfort. Our result suggested that a curved knife is a reasonable option for transaortic septal myectomy in patients with obstructive LV hypertrophy.

A case of Heyde syndrome: resolution following aortic valve replacement.

Heyde syndrome is a triad of aortic stenosis, acquired coagulopathy, and anemia due to bleeding from intestinal angiodysplasia. Here we describe a case of this syndrome. An 80-year-old woman with severe aortic stenosis was referred to our department for an aortic valve replacement. She suffered from recurrent iron-deficiency anemia and required transfusions every 2 weeks. Gastroscopy and colonoscopy were normal with the exception of angiodysplasia without bleeding in the cecum. After aortic valve replacement her anemia was resolved. She was discharged on postoperative day 22. No transfusions were needed after the procedure. To date, her hemoglobin has remained stable at >10 mg/dL.

Long-Term Outcomes of Endovascular Aneurysm Repair in Patients Aged ≤70 Years.

Objectives: The efficacy of endovascular aneurysm repair (EVAR) against abdominal aortic aneurysm (AAA) in younger patients remains unknown. Hence, the current study aimed to investigate whether the aneurysm-related mortality rate of EVAR is acceptable among patients aged ≤70 years. Methods: Among 644 patients, 148 underwent EVAR (EVAR group), and 496 received open surgical repair (OSR group). The cumulative incidence rates of aneurysm-related death, any intervention, and serious aneurysm-related events after AAA repair were evaluated using the cumulative incidence function in the presence of competing risks. Results: The EVAR group had higher prevalences of several comorbidities, and overall survival for the EVAR group was significantly inferior to that of the OSR group. The cumulative incidence rates of aneurysm-related death, any intervention, and serious aneurysm-related events at 5 years were 1.5%, 11.7%, and 6.4% in the EVAR group and 1.3%, 5.3%, and 5.9% in the OSR group, respectively. EVAR was not a significant prognostic factor of aneurysm-related mortality and serious aneurysm-related events. However, it was an independent poor prognostic factor of any intervention. Conclusion: EVAR was not a significant prognostic factor of aneurysm-related mortality and serious aneurysm-related events. Therefore, it demonstrated acceptable procedure-related long-term outcomes, at least in high-risk young patients.

Successful conservative treatment for left ventricular free wall rupture after acute myocardial infarction.

Left ventricular free wall rupture (LVFWR) is a rare but fatal complication of acute myocardial infarction (AMI). An 81-year-old female patient with several cardiovascular risk factors presented to the emergency department with symptoms of developing a chronic stomachache and cold sweat. An echocardiograph showed wall motion abnormalities from the lateral to posterior wall, as well as pericardial effusion containing clots of up to 17 mm in the posterior wall that indicated LVFWR after AMI. Although she was conscious after being brought to the initial care unit, she suddenly lost consciousness and fell into electromechanical dissociation (EMD). Endotracheal intubation was immediately initiated and her pericardial drainage and intra aortic balloon pump (IABP) placement, and hemodynamics recovered. Although she had 100% obstruction in the left circumflex artery (LCX) #12 on coronary angiography (CAG), she was discharged to the Intensive Care Unit (ICU) without percutaneous coronary intervention (PCI). Conservative treatment such as intubation, sedation, pericardiocentesis and strict blood pressure management as well as treatment by IABP long-term support led to the patient being uneventfully discharged after 60 days.

Epicardial atrial mapping can predict elimination of chronic atrial fibrillation after the box pulmonary vein isolation during mitral valve surgery.

BACKGROUND: The pulmonary veins (PV) and posterior left atrium (LA) may contribute to the occurrence and maintenance of atrial fibrillation (AF). We evaluated whether simple epicardial electrophysiological mapping can predict elimination of chronic AF after the box PV isolation procedure. METHODS AND RESULTS: Using a computerized 48-channel mapping system, we performed intraoperative atrial mapping in 16 patients with chronic AF associated with mitral valve (MV) disease. Patients' ages ranged from 48 to 76 years (mean, 61.4 years). AF duration ranged from 1 to 16 years (mean, 7.5±5.4 years). Simple box PV isolation was performed during the MV operation. Regular and repetitive activation was found in the LA of 12 of 16 patients, and irregular and chaotic activation was found in both atria in 4 of 16 patients; 12 patients with regular and repetitive activation of the LA were treated by box PV isolation and the other 4 patients with irregular and chaotic activation in both atria did not recover sinus rhythm after this procedure. AF-free rate was significantly higher in patients with regular and repetitive activation of the LA (P<0.01). CONCLUSIONS: Box PV isolation was effective in the treatment of chronic AF associated with MV disease. Epicardial atrial mapping may predict elimination of AF after the box PV isolation.