Bipolar radiofrequency ablation for re-entrant ventricular tachycardia of right bundle branch block and left bundle branch block morphologies with the common slow conduction zone at the left ventricular summit: a case report.

Background: The left ventricular (LV) summit has anatomical limitations, so the detailed mapping is difficult. Therefore, the mechanism of ventricular tachycardia (VT) originating from the LV summit is not well understood. Case summary: A 70-year-old man had VTs with right bundle branch block (VT1 and VT3) and left bundle branch block (VT2) morphologies originating from the left ventricular summit (LV summit). During the VT2 and VT3, fragmented potentials, which occurred earlier than the QRS onset, were recorded from bipolar electrodes of a catheter at the anterior intraventricular vein (AIV). By pacing from right ventricular apex, constant and progressive fusion were observed. During the entrainment pacing, the fragmented potentials in the AIV catheter were activated orthodromically and those in the His bundle were activated antidromically. In addition, there were two components of the ventricular electrogram at the LV summit area with the interval of more than 100 ms during the VTs. We performed bipolar radiofrequency ablation between the LV endocardium and AIV, and the VTs became non-inducible. Discussion: Non-sustained VT/premature ventricular contraction originating from LV summit is generally considered to occur due to abnormal automaticity or triggered activity. In contrast, using entrainment technique, we demonstrated that the VTs with multiple morphologies were sustained with a re-entrant mechanism. Fragmentated potentials recorded in the AIV catheter were activated orthodromically with the entrainment pacing, indicating the slowly conducting isthmus. The intramural VT substrate was also suggested with a prolonged conduction time between the two ventricular components during the VTs.

Impact of COVID-19 pandemic on emergency medical system and management strategies in patients with acute coronary syndrome.

The global coronavirus disease-2019 (COVID-19) pandemic is associated with reduced rate of percutaneous coronary intervention (PCI). However, there were a few data showing how emergency medical system (EMS) and management strategies for acute coronary syndrome (ACS) changed during the pandemic. We sought to clarify changes on characteristics, treatments, and in-hospital mortality of patients with ACS transported via EMS between pre- and post-pandemic. We examined consecutive 656 patients with ACS admitted to Sapporo City ACS Network Hospitals between June 2018 and November 2021. The patients were divided into pre- and post-pandemic groups. The number of ACS hospitalizations declined significantly during the pandemic (proportional reduction 66%, coefficient -0.34, 95% CI -0.50 to -0.18, p < 0.001). The median time from an EMS call to hospital was significantly longer in post-pandemic group than in pre-pandemic group (32 [26-39] vs. 29 [25-36] min, p = 0.008). There were no significant differences in the proportion of patients with ACS receiving PCI, and in-hospital mortality between the groups. The COVID-19 pandemic had a significant impact on EMS and management in patients with ACS. Although a significant decline was observed in ACS hospitalizations, the proportion of patients with ACS receiving emergency PCI remained during the pandemic.

Intravascular ultrasound findings of the protrusion of the EXOSEAL plug that caused acute limb ischemia.

Vascular closure devices have become popular for rapid hemostasis and early ambulation. However, there are a few reports of complications. We presented a case with acute limb ischemia caused by the protrusion of the EXOSEAL plug into the vessel. Intravascular ultrasound imaging helped determine the plug that caused the occlusion.

Long-term follow-up of the red density pilot trial: a basis for long-term prediction of sustained clinical remission in ulcerative colitis?

Red density (RD) technology is an automated operator-independent endoscopic scoring system for disease activity in ulcerative colitis (UC). In this retrospective analysis we aimed to assess the predictive value of the RD sore for sustained clinical remission. All 39 patients from the RD pilot trial were evaluated for clinical outcome in a 5-year period. The highest RD score was considered for Receiver operating characteristic (ROC) analysis to determine the cut-off of the RD for the composite endpoint of treatment failure (defined as mortality, colectomy, hospitalizations, flares and UC therapy changes). Statistical significance was considered P < 0.05. Reassessment of the RD score was possible in 36 patients. The composite endpoint was reached in 17 of 39 patients. ROC analysis for clinical remission showed a RD cut-off of 65, area under the ROC was 0.68, sensitivity of 0.71, and a specificity of 0.63. A RD score of ≥ 65 demonstrated a statistically non-significant increase in composite endpoint (hazard ratio 0.49 (95% confidence interval 0.1871-1.280); P = 0.1453). In conclusion, the RD score may be an independent predictor of clinical remission in patients with UC for the disease course up to 5 years, but results of the ongoing PROCEED-UC trial are to awaited for definite conclusions.

Dual countertraction for extraction of abandoned leads with severe lead-to-lead adhesion.

Note that firm adhesion between the atrial lead near the proximal electrode and the ventricular lead is present. Simultaneous application of countertraction from the femoral and jugular workstation, i.e. dual countertraction, liberated the two leads from the adhesion.

A single premature stimulation from the para-Hisian region unmasked negative involvement of the left anterior fascicle in the verapamil-sensitive ventricular tachycardia with a right bundle branch block and right-axis deviation.

A 33-year-old man had verapamil-sensitive ventricular tachycardia (VT) with a right bundle branch block (RBBB) and right axis deviation. Programmed stimulation from the para-Hisian region induced ventricular tachycardias (VT1 or VT2). VT1 was entrained during pacing from the para-Hisian region. A single para-Hisian stimulation antidromically captured the proximal portion of the left anterior fascicle (LAF), but the cycle length of VT2 remained unchanged. This observation indicated that the upper limb of the LAF was a bystander of the reentry circuit. We have clarified this mechanism with applying a single premature stimulation from the para-Hisian region.

Automatic, computer-aided determination of endoscopic and histological inflammation in patients with mild to moderate ulcerative colitis based on red density.

BACKGROUND: The objective evaluation of endoscopic disease activity is key in ulcerative colitis (UC). A composite of endoscopic and histological factors is the goal in UC treatment. We aimed to develop an operator-independent computer-based tool to determine UC activity based on endoscopic images. METHODS: First, we built a computer algorithm using data from 29 consecutive patients with UC and 6 healthy controls (construction cohort). The algorithm (red density: RD) was based on the red channel of the red-green-blue pixel values and pattern recognition from endoscopic images. The algorithm was refined in sequential steps to optimise correlation with endoscopic and histological disease activity. In a second phase, the operating properties were tested in patients with UC flares requiring treatment escalation. To validate the algorithm, we tested the correlation between RD score and clinical, endoscopic and histological features in a validation cohort. RESULTS: We constructed the algorithm based on the integration of pixel colour data from the redness colour map along with vascular pattern detection. These data were linked with Robarts histological index (RHI) in a multiple regression analysis. In the construction cohort, RD correlated with RHI (r=0.74, p<0.0001), Mayo endoscopic subscores (r=0.76, p<0.0001) and UC Endoscopic Index of Severity scores (r=0.74, p<0.0001). The RD sensitivity to change had a standardised effect size of 1.16. In the validation set, RD correlated with RHI (r=0.65, p=0.00002). CONCLUSIONS: RD provides an objective computer-based score that accurately assesses disease activity in UC. In a validation study, RD correlated with endoscopic and histological disease activity.

Early surgery with aggressive surgical approach to improve 6-month outcomes in patients with active infective endocarditis: contribution of cerebral preoperative magnetic resonance imaging.

OBJECTIVES: We investigated the hypothesis that early surgery for infective endocarditis (IE) attenuates the rate of death or embolic events and does not increase the rate of relapse or postoperative valvular dysfunction (PVD) at 6 months. METHODS: 21 consecutive patients who underwent surgical treatment of IE were prospectively included. We assessed 6-month postoperative clinical outcomes by comparing early surgery (Group E, surgery within 72 h) and conventional treatment (Group C). Nine patients (43%) were assigned to Group E based on a combination of preoperative evaluation parameters, including the findings of cerebral magnetic resonance imaging (MRI), which was performed in all patients with left-sided IE. RESULTS: Six surgical plans (5 advancements and 1 postponement) were modified by routine MRI. Although preoperative echocardiography did not confirm all annular invasions, the rate of periannular infection, which was treated by pericardial annular patch plasty (56%) in patients with native-valve IE, was higher in Group E than C (P = 0.006). Early surgery based on MRI findings resulted in no postoperative embolic events or cerebral bleeding. The 6-month mortality rate was 0% in both groups, although the calculated 6-month IE mortality rate was 49.2 ± 25% and 28.8 ± 18%, respectively. No recurrence of IE or PVD occurred in Group E. The 6-month rate of freedom from composite events was 100% in Group E. CONCLUSIONS: Aggressive treatment (periannular resection and disuse of a prosthetic annuloplasty ring) and optimal antibiotic therapy based on intraoperative microorganisms, even in patients who underwent early surgery, reduced the 6-month relapse and PVD rates.

Critical takotsubo cardiomyopathy complicated by ventricular septal perforation.

An 81-year-old woman was admitted with chest pain. An electrocardiogram demonstrated ST segment elevation in leads II, III and aVF, and echocardiography revealed left ventricular apical asynergy with a left-to-right ventricular shunt. Meanwhile, emergent coronary angiography showed no significant coronary artery stenosis, whereas left ventriculography indicated apical ballooning and a left-to-right ventricular shunt. We therefore diagnosed the patient with Takotsubo cardiomyopathy complicated by ventricular septal perforation and cardiogenic shock. An electrocardiogram disclosed a prolonged QT interval over time, and the patient became hemodynamically stable under treatment with inotropes; however, she suddenly developed fatal ventricular fibrillation three days after hospitalization. Takotsubo cardiomyopathy complicated by ventricular septal perforation is a critical condition that requires careful monitoring.

Effects of angiotensin-converting enzyme inhibition and angiotensin II type 1 receptor blockade on beta-adrenoceptor signaling in heart failure produced by myocardial Infarction in rabbits: reversal of altered expression of beta-adrenoceptor kinase and G i alpha.

Both angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 (AT1) receptor blockers have been demonstrated to improve symptoms and prognosis in heart failure (HF). We compared the effects of ACE inhibition and AT1 receptor blockade on myocardial beta-adrenoceptor desensitization in rabbits with HF established 3 weeks after myocardial infarction (MI) with left circumflex coronary artery ligation. Rabbits with MI were randomized to no treatment, the ACE inhibitor temocapril (0.5 mg/kg/day) or AT1 receptor blocker valsartan (3 mg/kg/day). Echocardiographic examinations showed that, relative to rabbits with untreated MI, rabbits receiving temocapril or valsartan had a limitation of cardiac remodeling and prevention of the development of systolic dysfunction. Circulating plasma norepinephrine levels that were markedly elevated in MI animals were strongly inhibited by temocapril or valsartan therapy. beta-Adrenoceptor density, beta-adrenoceptor proportion showing high-affinity agonist binding, and basal and isoproterenol-stimulated adenylate cyclase activities were significantly reduced in MI rabbits. These defects were similarly reversed by temocapril or valsartan. Importantly, as found in human HF, myocardial protein levels of beta-adrenoceptor kinase 1 and G(i alpha) were significantly elevated in MI rabbits, suggesting that these molecules are contributing to the defects in myocardial beta-adrenoceptor signaling. The expression levels of these molecules were normalized equally by both treatments. The results suggest that pharmacologically different interventions in the renin-angiotensin system can equivalently improve the derangements in the beta-adrenoceptor signaling system in the failing heart. This may be important for the beneficial effects of these agents in HF.