A successful bridge to recovery with Impella 5.0 and subsequent hybrid cardiac resynchronization therapy in systemic right ventricle failure: a case report

Background　Impella 5.0 is currently used as a temporary mechanical circulatory support device in cardiogenic shock (CS). However, Impella 5.0 implantation for the systemic right ventricle (sRV) has not been well documented. Case summary　A 50-year-old man with atrial switch for dextro-transposition of the great arteries was transferred to our hospital for the treatment of embolic acute myocardial infarction of the left main trunk lesion with CS. To stabilize haemodynamics, we implanted Impella 5.0 via the left subclavian artery in the sRV. After optimal medical therapy initiation and gradual weaning of Impella 5.0, Impella 5.0 was successfully explanted. An electrocardiogram was obtained, which showed complete right branch block with a QRS duration of 172 ms. Acute invasive haemodynamic evaluation of cardiac resynchronization therapy (CRT) pacing showed that dP/dt increased from 497 to 605 mmHg/s (21.7% improvement), and hybrid cardiac resynchronization therapy defibrillator (CRTD) with a sRV epicardial lead was subsequently implanted. The patient was discharged without inotropic support. Discussion　Coronary artery embolism is a rare but serious complication of dextro-transposition of the great arteries after atrial switch operations. Impella 5.0 implantation is a feasible bridge strategy for refractory CS due to sRV failure. Although CRT implantation in patients with sRV is controversial, an acute invasive haemodynamic evaluation can help assess its potential benefits

Characterization of xenoantiserum produced against B cell acute lymphoblastic leukemia cell line

Antiserum was produced in white rabbit by intravenously injecting living cells of a B cell acute lymphoblastic leukemia (ALL) line (BALL-1). The reactivity of the antiserum against various lymphoid cell lines was examined by membrane immunofluorescence after appropriate absorption. Serum absorbed with non-T, non-B (NALL-1) and T-ALL (TALL-1) cells recognized B cell antigens distinct from Ia-like antigens on both normal and neoplastic B cells. After further absorption with tonsillar cells or normal B cell line (KO-HL-3), it reacted only with BALL-1 cells and did not react with other leukemia/lymphoma and normal B cell lines. The serum absorbed with tonsillar cells reacted only with BALL-1 and some B cell lines. Thus we were able to obtain antisera with specificity to B cell antigen, B-ALL antigen, and B cell line antigen.</p

Quantification of Lung Perfusion Blood Volume in Dual-Energy Computed Tomography in Patients with Pulmonary Hypertension

Dual-energy computed tomography (DECT) is a promising technique for the assessment of the lung perfused blood volume (LPBV) in the lung parenchyma. This study was performed to compare the LPBV by DECT of patients with pulmonary hypertension (PH) and controls and to evaluate the association between the LPBV and the perfusion ratio derived by lung perfusion scintigraphy. This study involved 45 patients who underwent DECT (25 patients with PH and 20 controls). We measured the total LPBV and distribution of the LPBV in each lung. The total LPBV was significantly lower in the PH group than the control group (38 +/- 9 vs. 45 +/- 8 HU, p = 0.024). Significant differences were observed between the LPBV of the upper lung of the PH and control groups (34 +/- 10 vs. 47 +/- 10, p = 0.021 and 37 +/- 10 vs. 47 +/- 8, p < 0.001). A significant correlation was observed between the LPBV and the lung perfusion scintigraphy. A lower total LPBV and lower LPBV of the upper lung as detected by DECT might be specific findings of PH

Improvement of lung function and pulmonary hypertension after pulmonary aneurysm repair: case series

Pulmonary artery aneurysms (PAA) can be complicated with pulmonary arterial hypertension (PAH), causing sudden death due to PA rupture and dissection. Because treatment with PAH-targeted drugs does not always prevent PAA progression, prophylactic surgical repair of the PAA seems a promising alternative. However, although it avoids rupture and dissection of the PAs, additional benefits have not been forthcoming. We therefore present two patients with co-existing PAH and a PAA who underwent surgical repair of the aneurysm. Following the surgery, their lung function and pulmonary hypertension improved. Optimal treatment of PAA remains uncertain, however, with no clear guidelines regarding the best therapeutic approach. This case series provides physicians with reasons to repair PAA surgically in patients with PAH

Pregnancy with Fontan circulation: A report of case series in Japan

Owing to new surgical procedures and medications, more women who have undergone the Fontan procedure reach childbearing ages. We report five cases of pregnancy with Fontan circulation. Case 1 had subchorionic hematoma (SCH), fetal growth restriction (FGR), and preterm labor (PTL). She delivered a 1073 g infant via cesarean section at gestation week 28 because of hemorrhagic shock. Case 2 delivered 2142 g and 2232 g infants at gestation weeks 37 and 36, respectively. She had FGR, PTL, and postpartum hemorrhage (PPH). Case 3 had SCH, PTL, and heart failure. At 36 weeks, labor was induced and she delivered a 2546 g infant by vacuum extraction with epidural analgesia. Cases 4 and 5 resulted in miscarriage. All subjects experienced obstetrical complications. This report discusses pregnant women with Fontan circulation by focusing on affected Japanese women. <Learning objective: More women who have undergone the Fontan procedure reach childbearing ages due to the new surgical procedures and medications. We report five cases and all of them experienced obstetrical complications. Anticoagulation might be one of the causes of postpartum hemorrhage. Labor epidural analgesia could contribute to minimized dynamic circulatory changes during labor. This report can be the literature regarding pregnant women with Fontan circulation in Japan.

Enhancement of pacing function by HCN4 overexpression in human pluripotent stem cell-derived cardiomyocytes

Background The number of patients with bradyarrhythmia and the number of patients with cardiac pacemakers are increasing with the aging population and the increase in the number of patients with heart diseases. Some patients in whom a cardiac pacemaker has been implanted experience problems such as pacemaker infection and inconvenience due to electromagnetic interference. We have reported that overexpression of HCN channels producing a pacemaker current in mouse embryonic stem cell-derived cardiomyocytes showed enhanced pacing function in vitro and in vivo. The aim of this study was to determine whether HCN4 overexpression in human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) can strengthen the pacing function of the cells. Methods Human HCN4 was transduced in the AAVS1 locus of human induced pluripotent stem cells by nucleofection and HCN4-overexpressing iPSC-CMs were generated. Gene expression profiles, frequencies of spontaneous contraction and pacing abilities of HCN4-overexpressing and non-overexpressing iPSC-CMs in vitro were compared. Results HCN4-overexpressing iPSC-CMs showed higher spontaneous contraction rates than those of non-overexpressing iPSC-CMs. They responded to an HCN channel blocker and beta adrenergic stimulation. The pacing rates against parent iPSC line-derived cardiomyocytes were also higher in HCN4-overexpressing iPSC-CMs than in non-overexpressing iPSC-CMs. Conclusions Overexpression of HCN4 showed enhancement of I-f current, spontaneous firing and pacing function in iPSC-CMs. These data suggest this transgenic cell line may be useful as a cardiac pacemaker