[Heart Transplantation for Older Patients].

The number of older donors is increasing in the limited number of donors in Japan. The number of older donors is increasing, and recipients are also ageing as the waiting period for transplantation becomes longer. The age of 60 years is one of the most important criteria for heart transplantation in Japan. Forty-two heart transplantations performed in our institution, and 12 cases were from donors aged over 60 years and seven recipients were older than 60 years at the time of transplantation. In four cases, both donor and recipient were over 60 years of age. All of these patients were discharged home after transplantation. As the number of older donors and recipients is expected to increase in the future, the number of marginal cases based on the status of not only the donor but also the recipient is expected to increase. The evaluation of coronary lesions and the identification of comorbid diseases, including malignant diseases, will become more important. A positive and careful overall decision at the time of transplantation is essential.

Fatal Pulmonary Hemorrhagic Infarction Caused by Pulmonary Vein Thrombotic Occlusion During Venoarterial Extracorporeal Membrane Oxygenation.

A 20-year-old man with arrhythmogenic right ventricular cardiomyopathy (ARVC) was resuscitated from ventricular fibrillation. He was transferred to our hospital because of progressive multiorgan dysfunction despite mechanical circulatory support with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) and intra-aortic balloon pump (IABP). At admission to our hospital, chest X-ray showed bilateral complete lung opacification, and echocardiography revealed a massive thrombus occupying the left atrium (LA) and left ventricle (LV). Conversion to central ECMO with transapical LV venting and thrombectomy were performed. The huge LA thrombus occluded all pulmonary veins (PVs). Despite the surgery and intensive care, complete lung opacity remained, and he died of multiorgan failure associated with sepsis. Autopsy demonstrated bilateral pulmonary multiple red infarctions, and histopathology showed alveolar wall necrosis with extensive hemorrhage, confirming a diagnosis of pulmonary hemorrhagic infarction. Extensive pulmonary infarction was attributable to PV occlusion due to massive LA thrombus. PV thrombosis should be considered when refractory lung opacities are encountered during VA-ECMO and necessitates early intervention.

Aortic root morphology can cause early bioprosthetic valve failure of externally mounted pericardial bioprosthesis.

A 73-year-old woman with a narrow aortic root had undergone aortic valve replacement with a 19-mm Mitroflow valve. Aortic annular enlargement with Manouguian's technique was performed, and the bioprosthesis had been implanted on the tilt in a supra-annular position. Four years after the implantation, echocardiography showed a significant de novo aortic regurgitation, which had not been detected 1 year earlier. In the reoperation, the left coronary leaflet of the bioprosthesis had attached and fused to the wall of the sinus of Valsalva, causing deformation of the valve leaflet and a commissural gap between the left and right coronary leaflets, which appeared to have caused the de novo aortic regurgitation. We assessed the cause of early valve deterioration by focusing on the morphology of the aortic root. Preoperative understanding of the aortic root morphology would help to avoid early valve dysfunction for aortic valve replacement with an externally mounted bioprosthesis.

Efficacy of preoperative electrocardiographic-gated computed tomography in predicting the accurate aortic annulus diameter in surgical aortic valve replacement.

OBJECTIVE: Electrocardiographic (ECG)-gated computed tomography (CT) can be used to determine which valve and size should be used in transcatheter aortic valve replacement (TAVR). It is beneficial to predict the accurate annulus diameter in surgical aortic valve replacement (SAVR), which can help in determining the surgical strategy. We aimed to compare the predicted aortic annulus size with the actual annulus size measured intraoperatively and to examine its validity. METHODS: A total of 88 patients underwent isolated or concomitant SAVR in 2018 at our hospital. The study population consisted of 45 patients who underwent preoperative CT assessment and intraoperative measurement. The perimeter- and area-derived diameters at the level of basal attachments were determined using CT, and the lower value among the two was defined as the predicted aortic annulus (CTpredict). The predicted aortic annulus (TTEpredict) was measured by transthoracic echography in the parasternal long-axis view. An actual-sized ball sizer was inserted into the annulus intraoperatively. True annulus size was determined as the labeled size that just fits on the annulus, and labeled size plus 1 mm was determined as one that passes through the annulus. RESULTS: There was better agreement with minimal bias between CTpredict and true annulus size as demonstrated in the Bland-Altman analysis with an intraclass correlation coefficient of 0.796 compared with TTEpredict. CONCLUSION: ECG-gated CT is also helpful in predicting the annulus diameter even in patients undergoing SAVR. This has important clinical implications for planning SAVR, including the surgical approach.

Chronologic Changes in Residual False Lumen Under Continuous-Flow Circulation.

We experienced a rare case of intraoperative type A aortic dissection during HeartMate II (Abbott, Chicago, IL) implantation and subsequently performed emergent total aortic arch replacement. Periodic follow-up computed tomography confirmed that the residual false lumen after the aortic repair had gradually thrombosed over time regardless of sufficient antithrombotic therapy. We analyzed the chronologic changes in the false lumen morphology, showing transient enlargement of the aortic diameter 1 year postoperatively and then a reduction at 3 years postoperatively. We report on the fate of residual false lumen after aortic repair under continuous-flow left ventricular assist device circulation.

A staged surgical strategy for cardiogenic shock and iatrogenic ventricular septal perforation due to a malpositioned catheter.

A 59-year-old woman fell into cardiogenic shock due to acute myocardial infarction with total occlusion of the left anterior descending artery. Although intra-aortic balloon pump was inserted and a coronary stent was placed, she went into cardiopulmonary arrest and percutaneous veno-arterial extracorporeal membrane oxygenation (ECMO) was initiated. She was transferred to our hospital after drainage for pericardial effusion. Computed tomography revealed the drainage catheter lying through the right ventricular free wall and the ventricular septum, and leading into the left ventricle. She showed multiple organ failure and disseminated intravascular coagulation syndrome due to insufficient ECMO flow. Conversion to central ECMO after catheter removal was performed and her general condition improved; however, ventricular septal shunt remained. Repair of the perforation and ECMO removal was performed 15 days after the first operation. The combination of optimal mechanical circulatory support and the staged surgical repair contributed to her dramatic recovery.

Determinants of Changes in Arterial Stiffness after Thoracic Endovascular Aortic Repair.

BACKGROUND: Aortic stent grafting can cause aortic stiffening and increase pulse wave velocity (PWV), which can potentially affect long-term cardiovascular outcomes. The aim of this study was to clarify the factors contributing to increases in PWV after thoracic endovascular aortic repair (TEVAR). METHODS: We included 64 patients with thoracic aortic pathology (51 men; mean age, 73 years) who underwent elective TEVAR, in this study. TEVAR was performed for degenerative aortic aneurysm (n = 43) or aortic dissection (n = 21), and the treatment length was 175 ± 52 mm. Brachial-ankle PWV (baPWV) was obtained before and 1 week after TEVAR. Univariable and multivariable logistic regression analyses were used to determine the predictors of increases in baPWV of ≥100 cm/sec after TEVAR. RESULTS: baPWV increased from 1,851 ± 392 cm/sec to 2,047 ± 479 cm/sec, and the change in baPWV (ΔbaPWV) was 195 ± 339 cm/sec (95% confidence interval, 111-280). Thirty-seven patients (58%) had ΔbaPWV ≥100 cm/sec after TEVAR. In the multivariable analysis, in addition to Δheart rate and Δsystolic blood pressure, age (odds ratio, 1.21/year; 95% confidence interval, 1.05-1.40) and coronary artery disease (odds ratio, 12.0; 95% confidence interval, 1.20-121) were independent determinants of ΔbaPWV ≥100 cm/sec after TEVAR, whereas ΔbaPWV ≥100 cm/sec was not associated with treatment length or device type. CONCLUSIONS: TEVAR was associated with PWV progression, especially in older patients with coronary artery disease, whereas treatment length or device type was not a predictor of PWV progression after TEVAR.

Preoperative distal aortic diameter is a significant predictor of late aorta-related events after endovascular repair for chronic type B aortic dissection.

OBJECTIVES: Long-term therapeutic effects of thoracic endovascular aortic repair (TEVAR) for chronic type B aortic dissection remain controversial. This study aimed to evaluate the possible predictors of late aortic rupture and re-interventions after TEVAR. METHODS: We retrospectively reviewed the operative outcomes of 40 patients who underwent TEVAR for chronic type B aortic dissection at Kyushu University Hospital. During a mean follow-up period of 39.2 months, we assessed aortic morphology via computed tomography and then employed a multivariable Cox regression analysis in an attempt to identify the predictors of late aorta-related events. RESULTS: The early success rate of TEVAR was 100%. During the follow-up, however, three patients died from aortic rupture. Eight patients required aortic re-intervention, including thoraco-abdominal aortic graft replacement, repeated TEVAR, total arch replacement and EVAR. Multivariable Cox regression analysis revealed that the preoperative maximum distal aortic diameter was a significant predictor of late aorta-related events. The cutoff value of the distal aortic diameter was 40 mm. Freedom from aorta-related events was 94.6% at 1 year and 78.3% at 3 years. The survival rate was not significantly different despite the re-intervention. CONCLUSIONS: TEVAR is an effective treatment for chronic type B dissection, with acceptable mid-term results. The preoperative distal aortic diameter is a significant risk factor for late aorta-related events. When the maximum distal aortic diameter is ≥ 40 mm, a therapeutic strategy should be developed taking into consideration the possible need for aortic re-intervention.

Pneumopericardium suggesting left ventricular assist device-related gastrointestinal complication.

We report an uncommon case of ventricular assist device-related infection and resultant fistula formation into the gastrointestinal tract. A 69-year-old man, who had undergone implantation of a HeartMate II 1 year earlier secondary to ischemic cardiomyopathy, presented to our hospital with a high fever. Computed tomography showed unusual gas collection around the heart apex (i.e., pneumopericardium), which had not been detected before. The patient developed sudden melena with fresh blood without abdominal symptoms 1 month after beginning antibiotic therapy. Emergent colonoscopy showed that the HeartMate II strain relief of the inflow conduit had penetrated the transverse colon. We immediately performed laparoscopy-assisted left-sided hemicolectomy and found intraoperatively that a fistula had formed between the splenic flexure and the pericardial cavity. Subsequently, the HeartMate II system was totally explanted and replaced with an Impella 5.0 for alternative hemodynamic support. In our patient, pneumopericardium might have been an early sign of a hidden gastrointestinal complication. Our experience is a caution for clinicians who manage patients with ventricular assist device support via the apex.

Successful off-pump surgical release for extrinsic compression of outflow graft obstruction of a left ventricular assist device.

A 36-year-old woman had received support with the Jarvik 2000 left ventricular assist device for 3 years. Cardiac computed tomography revealed outflow graft obstruction, which appeared as external compression of the outflow graft. The patient underwent surgical release of the obstruction after resternotomy. Yellow sediment had become encrusted in the enclosed space between the covering graft and outflow graft and appeared to have been derived from plasma contents. Successful release of the obstruction was achieved by cutting open the covering graft without cardiopulmonary bypass. Neither pump exchange nor outflow graft exchange was required. This off-pump surgery can be a beneficial procedure in terms of less invasiveness and good curability.

Jarvik 2000 axial flow ventricular assist device in right single ventricle after Fontan operation.

We present a case of successful ventricular assist device support in a 13-year-old female diagnosed with right single ventricle, asplenia, dextrocardia, who had undergone a Fontan operation at 4 years old in an associated children hospital. She underwent placement of Jarvik 2000 axial flow ventricular assist device to the morphologic right ventricle which worked as systemic ventricle. The postoperative course was not eventful. She was waiting for heart transplantation attending high school 3 years after implantation.

Single-stage hybrid total arch replacement for extended arch aneurysms.

OBJECTIVE: The therapeutic strategy for extended aortic arch aneurysms remains controversial and has changed substantially since thoracic endovascular aortic repair was introduced. We applied single-stage hybrid (s-hybrid) total arch replacement (TAR), which involved ascending aorta replacement and debranching of arch vessels, consecutively performed with thoracic endovascular aortic repair for extended arch aneurysms. The aim of this study was to investigate the short-term results of s-hybrid TAR and to clarify the benefit of this method. METHODS: We reviewed the operative results of 62 patients who underwent elective s-hybrid TAR or conventional TAR (c-TAR) through the median approach from 2008 to 2017. We used the s-hybrid approach in 15 patients and the c-TAR approach in 47 patients. In both groups, axillary arterial perfusion and selective antegrade cerebral perfusion under moderate hypothermia were applied for brain protection. We compared the perioperative outcomes of the two groups. RESULTS: We completed s-hybrid TAR in all 15 patients with extended aneurysms. The s-hybrid group required shorter times for myocardial ischemia, selective antegrade cerebral perfusion, and circulatory arrest of the lower body compared with the c-TAR group. The patients with complicated recurrent laryngeal nerve palsy and long ventilation support times were fewer in the s-hybrid group. No patient had substantial endoleaks or permanent paraplegia. The in-hospital mortality rates were 6.7% in the s-hybrid group and 0% in the c-TAR group. CONCLUSIONS: The s-hybrid TAR has the same or better perioperative outcomes compared with the c-TAR approach. For extended aneurysms, this technique could resolve the problem of respiratory failure induced by left thoracotomy and also resolve the problem of rupture during the waiting period in staged surgery.

HeartMate II Implantation Via Single Incisional Ministernotomy in a Small Young Woman.

We report a successful case of less invasive implantation of a HeartMate II in a small young woman. A 34-year-old woman, who developed refractory heart failure associated with chronic myocarditis, underwent implantation of a HeartMate II via T-shaped ministernotomy without any additional incisions. This approach has several unique advantages: all of the procedures can be operated in the same view in the usual fashion with minor modifications; some optional procedures can be easily added during the operation if necessary. To confirm the feasibility and versatility of this approach, we assessed the postimplant pump position by the radiographic parameters. The radiographic assessment showed that those parameters were not significantly different than those in our other normal body-sized patients. There were no adverse events associated with HeartMate II implantation during her follow-up. We consider that this approach has the feasibility and versatility, and can be an alternative approach in cases where the conventional approach is inappropriate for some reason.

Pediatric Biventricular Assist Device for Myocarditis and Complicated Left Ventricular Thrombus.

An 8-year-old girl presenting with fulminant myocarditis and cardiogenic shock underwent peripheral extracorporeal membrane oxygenation. She was switched to central extracorporeal membrane oxygenation because of inadequate venous drainage, and an echocardiogram showed left ventricular (LV) thrombus. She underwent removal of the LV thrombus with LV venting. An echocardiogram showed LV thrombus again 2 days later. The LV thrombus was again removed, and a biventricular assist device support was initiated to avoid further thrombus formation. The patient was completely weaned from mechanical circulatory support after 7 days. She recovered fully without any neurologic deficit.

Comparison of cardiac energetics after transcatheter and surgical aortic valve replacements.

OBJECTIVES: The effect of transcatheter aortic valve replacement (TAVR) on cardiac energetics has not been described. We compared changes in cardiac energetics after TAVR with those after surgical aortic valve replacement (SAVR). METHODS: We retrospectively estimated end-systolic elastance (Ees) and effective arterial elastance (Ea) using blood pressure and left ventricular (LV) volume obtained from echocardiography. LV efficiency [ventriculoarterial coupling (Ea/Ees) and the stroke work to pressure-volume area ratio (SW/PVA)] was calculated. Measurements were taken before, 1 week after and 1 year after bioprosthetic aortic valve replacement (TAVR, n = 56; SAVR, n = 61) in patients with severe aortic stenosis and preserved ejection fraction. RESULTS: Patients with TAVR had a lower aortic valve pressure gradient and larger stroke volume 1 week after the procedure than those with SAVR. Ea was more markedly decreased, and LV efficiency was significantly improved 1 week after TAVR (SW/PVA 68.1% ± 8.4% to 72.0% ± 8.5%, P < 0.001), but LV efficiency was unchanged 1 week after SAVR (SW/PVA 70.1% ± 7.4% to 69.1% ± 8.0%). LV efficiency was improved 1 year after both procedures (SW/PVA 75.5% ± 6.1% in TAVR; 74.7% ± 6.4% in SAVR). CONCLUSIONS: TAVR decreases the transvalvular pressure gradient further without deteriorating stroke volume in the early postoperative period, which is accompanied by early improvement in afterload and LV efficiency compared with SAVR. Improvement in LV efficiency at mid-term follow-up is satisfactory after both procedures.

Thoracic endografting increases cardiac afterload and leads to left ventricular hypertrophy in dogs.

OBJECTIVES: Aortic endografting can cause aortic stiffening. We aimed to determine the chronic effect of thoracic endografting on cardiac afterload, function and remodelling. METHODS: Eleven dogs were included, and all except 1 was successfully assessed [endograft, n = 5; sham operation (control), n = 5]. We deployed a stent graft in the descending aorta. The ascending aortic pressure and flow were measured, and aortic input impedance was obtained by frequency analysis to determine characteristic impedance and arterial compliance. Left ventricular pressure-volume relations were measured with an admittance catheter. Measurements were performed before, 10 min after and 3 months after endografting. Following euthanasia, we weighed the left ventricle of each dog and measured the cardiomyocyte cell size. RESULTS: Arterial compliance decreased from 0.47 ± 0.07 to 0.36 ± 0.06 and to 0.31 ± 0.05 ml/mmHg (both P < 0.01 versus baseline), and characteristic impedance increased from 0.11 ± 0.04 to 0.19 ± 0.05 and to 0.21 ± 0.04 mmHg/ml/s (both P < 0.01 versus baseline) 10 min and 3 months after endografting, respectively. Pressure-volume relation analysis showed that arterial elastance increased from 5.3 ± 1.0 to 6.7 ± 1.6 (at 10 min) and to 6.8 ± 1.0 mmHg/ml (at 3 months) (both P < 0.05 versus baseline), but end-systolic elastance and ventriculo-arterial coupling remained unchanged. Left ventricular weight to body weight ratio and left ventricular cardiomyocyte cell width in the endograft group were larger compared with the control's results (5.06 ± 0.27 g/kg vs 4.20 ± 0.49 g/kg, P = 0.009, 15.1 ± 1.7 µm vs 13.9 ± 1.5 µm, P = 0.02, respectively). CONCLUSIONS: The mid-term effect of the descending aortic endografting on left ventricular contractility and efficiency in canine normal hearts was minimal. However, endografting resulted in increased cardiac afterload and left ventricular hypertrophy.

Omental and deep inferior epigastric artery perforator flap coverage after heart transplantation to manage wide left ventricular assist device exposure with pocket infection.

Infection is a serious potential complication after left ventricular assist device (LVAD) implantation. In general, infection of the device pocket, with device exposure, should be managed by early device removal and heart transplantation. However, because of the small number of donors in Japan, accelerating access to heart transplantation is often difficult and the LVAD can be widely exposed during the waiting period. We report our experience of successful heart transplantation in a patient with a widely exposed LVAD with pocket infection. A 48-year-old man suffered from heart failure due to idiopathic dilated cardiomyopathy. An LVAD was implanted, but postoperative infection led to blood pump exposure. Heart transplantation was performed 4 months after LVAD exposure, at which time the epigastric skin defect measured 14 × 8 cm. The skin defect could not be closed after heart transplantation, so it was covered by an omental flap with split-thickness skin grafts. 7 days postoperatively, the peritoneal suture broke and the intestinal tract prolapsed outside the body. Reintroduction of the prolapsed intestinal tract and deep inferior epigastric artery perforator (DIEP) flap coverage of the omental flap were performed. The postoperative course was uneventful. There have been no reports of the management of wide skin defects in the presence of infection when heart transplantation is performed. Omental flap placement was useful for controlling long-lasting infection. An omental flap placed in a patient with a wide epigastric skin defect should be covered by durable skin flap, such as a DIEP flap, to avoid intestinal prolapse.

Thrombotic microangiopathy in a very young infant with mitral valvuloplasty.

BACKGROUND: Thrombotic microangiopathies (TMA) are microvascular occlusive disorders characterized by systemic or intrarenal platelet aggregation, thrombocytopenia, and red cell fragmentation. Post-operative TMA mostly occurs in adult patients with cardiovascular surgery, with the distinct pathophysiology from classical thrombotic thrombocytopenic purpura (TTP) although the exact pathophysiology remains unclear. CASE PRESENTATION: A one-month-old infant developed TMA after the initial surgery of double outlet right ventricle. ADAM metallopeptidase with thrombospondin type 1 motif 13 (ADAMTS13) activity was sustained (64%) with the undetectable inhibitor. Von Willebrand factor (VWF) multimer analyses showed absent high-molecular weight multimers. Echocardiography disclosed severe mitral regurgitation. The mitral valve repair 32 days after the initial valvuloplasty led to prompt resolution of TMA. These suggested that TMA occurred in association with valvulopathy-triggered turbulent shear flow, mechanical hemolysis and endothelial damage. The consumption of large VWF multimers might account for the vascular high shear stress shown in Heyde syndrome. CONCLUSION: The youngest case of post-operative TMA underscores the critical coagulopathy after the first surgical intervention for congenital heart disease.

Disuse Atrophy of the Aortic Valve After Left Ventricular Assist Device Implantation.

A 31-year-old woman underwent implantation of a DuraHeart left ventricular assist device as bridge to transplantation. Aortic insufficiency was not observed before implantation but developed after implantation and became severe approximately 2 years later. Macroscopically, the aortic valve excised during heart transplantation showed no morphologic alteration. Microscopically, the collagen fibers in the fibrosa layer and the elastic fibers in the ventricularis layer of the valve leaflets were reduced in number, with irregular arrangement. These characteristics can be explained by a disuse atrophic change, and may lead to a better understanding of the mechanism underlying the development of aortic insufficiency.