Impact of Coronary Artery Calcification in the Donor Heart on Transmitted Coronary Artery Disease in Heart Transplant Recipients

BACKGROUND

Coronary artery disease (CAD) after heart transplantation (HTx) develops as a combination of donor-transmitted coronary atherosclerosis (DTCA) and cardiac allograft vasculopathy. Assessing donor CAD before procurement is important. Because coronary artery calcification (CAC) is a predictor for CAD, donor-heart CAC is usually evaluated to estimate the risk of donor CAD. The usefulness of CAC for predicting DTCA, however, is not known. Methods and Results: Sixty-four HTx recipients whose donor underwent chest computed tomography before procurement or ≤2 weeks after HTx and who underwent coronary angiography and intravascular ultrasound (IVUS) ≤3 months after HTx were enrolled. Eight patients had CAC (CAC group) and 56 patients did not have CAC (no-CAC group). Patients in the CAC group were significantly older and had a higher prevalence of maximum intimal thickness (MIT) of the coronary artery ≥0.5 mm at initial IVUS than patients in the no-CAC group (100% vs. 55%, P=0.02). Adverse cardiac events and death were not significantly different. Everolimus tended to be used more often in the CAC group.

CONCLUSIONS

Donor-heart CAC is a significant predictor for MIT of the coronary artery ≥0.5 mm after HTx. The presence of CAC, however, is not associated with future cardiac events. The higher prevalence of everolimus use in the CAC group may have affected the results.

[Outpatient Care for Implantable Left Ventricular Assist Device Patients]

From 2005, 124 patients have received implantable left ventricular assist device (iVAD) in our institute, including HeartMate II (84), EVAHEART (17), Jarvik2000 (13), DuraHeart (9), HVAD (1). At February 2018, 60 patients were waiting for heart transplant with iVAD support. Multi-specialist team consisted of clinical engineer, VAD management specialist, nurse, transplant coordinator for recipient and physicians provide patients care. Thirty one percents returned to their social activity after iVAD implantation. 73% patients required rehospitalization for more than 1 time. Overall frequency of rehospitalization was 1.43 events per patient-year. Driveline infection was the most frequent reason and tended to repeat, accounted for 41% of overall rehospitalization. To reduce skin trouble around the driveline exit site causing driveline infection, we made a skin care outpatient clinic, cooperating with a certified nurse in wound, ostomy, and continence nursing (WOC). Besides, we utilize smartphones for remote advising system for patients to facilitate early diagnosis and precise care for driveline infection. A self-anticoagulation management device( Coag-check XS personal) enable us to give adequate anticoagulation therapy and to minimize bleeding and thromboembolic event. Additionally, establishment of psychosocial care promote patient's recovery of social status. With those strategies in outpatient care, we are trying to achieve successful quality of life of iVAD patients.

Reversible Cerebral Vasoconstriction Syndrome After Heart Transplantation: A Case Report

BACKGROUND

Reversible cerebral vasoconstriction syndrome (RCVS) is a transient cerebrovascular disorder putatively caused by some immunosuppressive agents.

CASE REPORT

We recently encountered a 47-year-old female patient diagnosed with dilated cardiomyopathy who developed RCVS after heart transplantation. A triple-drug regimen consisting of tacrolimus, mycophenolate mofetil, and a corticosteroid was started after surgery. On postoperative day (POD) 11, the patient developed a severe headache, although computed tomography of the head demonstrated no signs of hemorrhage or infarction. At first, both a painkiller and migraine drugs were regularly administered to the patient. On POD 21, however, she developed an unbearable headache with a visual field defect and mild hemiparesis of the right hand. Magnetic resonance imaging (MRI) of the brain revealed a cerebral infarction in the left occipital lobe with diffuse vasoconstriction of both the middle and posterior cerebral arteries. A diagnosis of RCVS was made and tacrolimus, a drug suspected to cause RCVS, was discontinued. In its place, two doses of basiliximab followed by everolimus, both of which are alternatives for tacrolimus, were given. The corticosteroid dose was also increased. Furthermore, to release vasoconstriction, both verapamil and diltiazem were administered. On POD 27, cerebrovascular constrictions were shown to be relieved on brain MRI and the patient's neurological symptoms subsequently almost completely diminished.

CONCLUSION

RCVS should always be considered as a cause of headache in heart transplant recipients because tacrolimus, an immunosuppressive agent, may trigger RCVS. This will allow rapid intervention that is essential for avoiding irreversible neurological deficits.

Clinical determinants of successful weaning from extracorporeal membrane oxygenation in patients with fulminant myocarditis

Aims

Patients with fulminant myocarditis (FM) often present with cardiogenic shock and require mechanical circulatory support, including extracorporeal membrane oxygenation (ECMO) and ventricular assist device (VAD) implantation. This study sought to clarify the determinants of successful weaning from ECMO in FM patients.

Methods and results

We studied 37 consecutive FM patients supported by ECMO as the initial form of mechanical circulatory support between January 1995 and December 2014 in our hospital. Twenty‐two (59%) patients were successfully weaned from ECMO, while 15 (41%) were not. There were significant differences in levels of peak creatine kinase and those of its MB isoform (CK‐MB), left ventricular posterior wall thickness (LVPWT), and prevalence of cardiac rhythm disturbances. Receiver operating characteristic curve analysis revealed that a peak CK‐MB level of 185 IU/L and LVPWT of 11 mm were the optimal cut‐off values for predicting successful weaning from ECMO (areas under the curve, 0.89 and 0.85, respectively). During the follow‐up [median 48 (interquartile range 8–147) months], 83% of FM patients who were weaned from ECMO survived, with preserved fractional shortening based on echocardiography. Of the 15 FM patients who were not weaned from ECMO, nine bridged to VAD, and only two were successfully weaned from VAD and survived.

Conclusions

These results indicate that myocardial injury, as evidenced by CK‐MB and LVPWT, and prolonged presence of cardiac rhythm disturbances are important clinical determinants of successful weaning from ECMO.

Paradoxical Reaction of Tuberculosis in a Heart Transplant Recipient During Antituberculosis Therapy: A Case Report

INTRODUCTION

Tuberculous paradoxical reactions (PRs) are excessive immune reactions occurring after antituberculosis (TB) treatment and are commonly observed in immunocompromised hosts such as patients infected with the human immunodeficiency virus.

CASE REPORT

We recently encountered a 63-year-old male heart transplant recipient who developed tuberculous PR after treatment for miliary TB. The patient had been receiving immunosuppressive therapy with cyclosporine and mycophenolate mofetil for over 15 years. The diagnosis of miliary TB was made based on the presence of intermittent fever and fatigue; thus, anti-TB treatments (isoniazid, levofloxacin, ethambutol, and pyrazinamide) were started, which led to rapid defervescence and regression of the granular shadow and pleural effusion. However, a new persistent fever and confused state developed 1 month after the anti-TB therapy was started. After excluding possible etiologies of the patient's symptom, a PR was suspected, and anti-TB drugs were continued; corticosteroids were added as anti-inflammatory agents. After that, he has shown a favorable course with long-term anti-TB chemotherapy.

CONCLUSION

A PR should always be considered when the patients' symptoms of tuberculosis re-exacerbate after an appropriate anti-TB therapy. A PR commonly occurs in patients with various immunologic conditions including heart transplant recipients.

Clinical Outcomes of Patients With the HeartMate II Left Ventricular Assist Device: A Single-center Experience From Japan

BACKGROUND

Left ventricular assist device (LVAD) therapy is the "gold standard" alternative therapy for patients with advanced heart failure. However, LVAD therapy is still uncommon in the Asia-Pacific region. Therefore, we aimed to elucidate the clinical outcomes of patients from Japan supported with the HeartMate II (HM-II) LVAD at our institution.

METHODS

Ninety-two patients (mean 44.3 ± 12.1 years, 68 men, average body mass index 1.65 ± 0.28 m²; 81 with nonischemic cardiomyopathy) who underwent HM-II implantation for bridge to transplantation (n = 91) or for destination therapy in a clinical study (n = 1) at the National Cerebral and Cardiovascular Center between April 2013 and October 2017 were enrolled in this analysis. Preoperatively, most patients (n = 73, 79%) had an INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profile of between level 2 and 4. Postoperatively, the average pump speed was 8602 ± 258 rpm and the hemodynamics were well compensated.

RESULTS

Adverse events consisted of 38 (41.3%) hemolysis, 30 (32.6%) major infection, 27 (29.3%) major bleeding (6 [6.5%] with gastrointestinal bleeding), and 18 (19.6%) neurologic dysfunction events. Eighteen patients underwent heart transplantation (HTx) after an average of 32.9 ± 8.9 months of VAD support, and overall survival at both 6 months and 3 years was 96.3%.

CONCLUSION

Clinical outcome among patients with HM-II at our institution is satisfactory for both survival and adverse events. The HM-II can provide effective hemodynamic support during the extremely long waiting period for HTx in Japan.

Heat Failure Phenotypes Induced by Knockdown of DAPIT in Zebrafish: A New Insight into Mechanism of Dilated Cardiomyopathy

The pathogenesis of heart failure associated with dilated cardiomyopathy (DCM) may result in part from adenosine triphosphate (ATP) dysregulation in the myocardium. Under these conditions, diabetes-associated protein in insulin-sensitive tissue (DAPIT), which is encoded by the upregulated during skeletal muscle growth 5 (USMG5) gene, plays a crucial role in energy production by mitochondrial ATP synthase. To determine whether USMG5 is related to the development of heart failure, we performed clinical and experimental studies. Microarray analysis showed that the expression levels of USMG5 were positively correlated with those of natriuretic peptide precursor A in the human failed myocardium. When endogenous z-usmg5 in zebrafish was disrupted using morpholino (MO) oligonucleotides, the pericardial sac and atrial areas were larger and ventricular fractional shortening was reduced compared to in the control MO group. The expression levels of natriuretic peptides were upregulated in the z-usmg5 MO group compared to in controls. Further, microarray analysis revealed that genes in the calcium signalling pathway were downregulated in the z-usmg5 MO group. These results demonstrate that DAPIT plays a crucial role in the development of heart failure associated with DCM and thus may be a therapeutic target for heart failure.

Donor-Transmitted Atherosclerosis Associated With Worsening Cardiac Allograft Vasculopathy After Heart Transplantation: Serial Volumetric Intravascular Ultrasound Analysis

BACKGROUND

The influence of preexisting donor-transmitted atherosclerosis (DA) on cardiac allograft vasculopathy (CAV) development remains unclear.

METHODS

We performed 3-dimensional intravascular ultrasound (3D-IVUS) analysis in 42 heart transplantation (HTx) recipients at 2.1 ± 0.9 months (baseline) and 12.2 ± 0.4 months post-HTx, as well as consecutive 3D-IVUS analyses up to 3 years post-HTx in 35 of the 42 recipients. Donor-transmitted atherosclerosis was defined as a maximal intimal thickness of 0.5 mm or greater at baseline. Changes in volumetric IVUS parameters were compared in recipients with (DA group) and without DA (DA-free group) at baseline, 1 year, and 3 years post-HTx.

RESULTS

Donor-transmitted atherosclerosis was observed in 57.1% of 42 recipients. The DA group exhibited a significantly greater increase in plaque volume at 1 year post-HTx (P < 0.001), leading to increased percent plaque volume (plaque volume/vessel volume, [%]) (P < 0.001) and decreased luminal volume (P = 0.021). Donor-transmitted atherosclerosis was independently associated with a greater increase in percent plaque volume during the first post-HTx year (P = 0.011). From 1 to 3 years post-HTx, the DA group underwent continuous reduction in luminal volume (P = 0.022). These changes resulted in a higher incidence of angiographic CAV at 3 years post-HTx in the DA group (58.8% vs 5.6%, P = 0.002).

CONCLUSIONS

This volumetric IVUS study suggests that DA correlates with the worsening change in CAV several years post-HTx. Donor-transmitted atherosclerosis recipients may require more aggressive treatment to prevent subsequent CAV progression.

Percutaneous Coronary Intervention and Coronary Artery Bypass Grafting in Heart Transplant Recipients With Transplant Coronary Arterial Vasculopathy

BACKGROUND

Transplant coronary arterial vasculopathy (TCAV) is a major cause of death after heart transplantation (HTx). Palliative coronary revascularization has been attempted in patients with severe TCAV; however, the outcome has not been fully elucidated.

METHODS

Ninety-six patients who were treated after HTx at our institute between 1999 and 2015 were screened for TCAV. TCAV was defined as >70% stenosis on coronary angiography (CAG) or a maximal intimal thickness of >0.5 mm in the right or left coronary arteries on intracoronary ultrasonography (IVUS). In the present study, the outcomes of patients with severe TCAV who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) were investigated.

RESULTS

TCAV containing donor-transmitted atherosclerosis was cumulatively found in 69 patients (71.9% of the total; mean age, 34.6 ± 13.1 years; 52 men; mean follow-up duration, 83.0 ± 60.4 months). Five (7.2%) and 64 (92.8%) of the 69 patients were diagnosed as having TCAV by use of CAG and IVUS, respectively. All 5 patients diagnosed by with the use of CAG underwent coronary revascularization between 1 and 236 months after HTx. Three patients underwent PCI with drug-eluting stents, with a primary success rate of 100%. No angiographic restenosis occurred in 2 patients at 31 and 36 months after PCI, respectively. Meanwhile, 2 patients underwent CABG. No peri-operative complications occurred, and all grafts were patent as assessed by use of CAG at 34 and 5 months after CABG.

CONCLUSIONS

Coronary revascularization was feasible and effective for severe TCAV with middle-term follow-up.

Low partial pressure of end-tidal carbon dioxide predicts left ventricular assist device implantation in patients with advanced chronic heart failure

BACKGROUND

This study aimed to clarify the prognostic impact of partial pressure of end-tidal carbon dioxide (PETCO₂) in patients with advanced chronic heart failure (HF).

METHODS

Forty-eight patients (mean age 43.1±11.9years, 32 males) with chronic HF (44 with non-ischemic and 4 with ischemic cardiomyopathy) were prospectively enrolled. Echocardiography, blood tests, pulmonary function testing, and PETCO₂ measurements were performed as noninvasive tests, whereas right heart catheterization and arterial blood gas analysis were conducted as invasive tests. The primary end point of this study was left ventricular assist device (LVAD) implantation or cardiac death.

RESULTS

Eighteen patients underwent LVAD implantation at the Interagency Registry for Mechanically Circulatory Support (INTERMACS) profile 3 during the follow-up period, and no patient died. PETCO₂ was significantly lower in a stepwise manner with New York Heart Association functional class (class I or II, 34.2±9.3mmHg vs. class III or IV, 27.7±2.5mmHg; p<0.001). Univariate and multivariate Cox proportional hazard models and time-dependent receiver operating characteristic curve analysis revealed that PETCO₂≤31mmHg is an independent noninvasive predictor of LVAD implantation. Univariable and multivariable linear regression analyses showed that pulmonary arterial pressure was independently and highly correlated with PETCO₂ (r²=-0.512, p<0.001).

CONCLUSIONS

Among various noninvasive clinical parameters investigated, PETCO₂ was the independent predictor of LVAD implantation at the INTERMACS profile 3 in patients with chronic HF. Pulmonary congestion may significantly contribute to decreases in PETCO₂ in patients with HF.

Successful treatment of near-fatal fulminant myocarditis using bi-ventricular assist device support

Fulminant myocarditis is a rare but fatal serious disease that may cause prolonged native cardiac dysfunction with multiorgan failure despite temporary mechanical circulatory support with percutaneous venoatrial extracorporeal membrane oxygenation (VA-ECMO) or intraaortic balloon pumping (IABP). A 26-year-old man with fulminant myocarditis developed life-threatening multiorgan failure after 8 days support by VA-ECMO and IABP. He was transferred to our institution with prolonged cardiac dysfunction on hospital day 8; massive pulmonary edema developed into severe pulmonary dysfunction. Immediately after admission, VA-ECMO and IABP were switched to a paracorporeal pneumatic left ventricular assist device (LVAD) and right centrifugal ventricular assist device with an ECMO circuit shunting from the right ventricle to the pulmonary artery (RVAD-ECMO). After intensive care focusing on respiratory dysfunction, ECMO was successfully weaned, and the right ventricular assist device was switched to a durable paracorporeal pneumatic right ventricular assist device. The paracorporeal bi-ventricular assist devices were finally replaced with an implantable non-pulsatile LVAD on hospital day 181. Currently, 1 year after discharge, the patient is at home awaiting heart transplantation. Combined LVAD and RVAD-ECMO appear to be useful for resolving severe pulmonary edema due to unnecessarily long VA-ECMO support as well as kidney or liver dysfunction caused by circulatory collapse.

Abstract WMP54: Cerebrovascular Accidents in Patients With a Left Ventricular Assist Device

Background: Cerebrovascular accidents (CVAs), including ischemic stroke, transient ischemic attack, and intracranial hemorrhage, are major and devastating complications of left ventricular assist devices (LVADs). However, little is known about their incidence and risk factors.

Materials and methods: We retrospectively reviewed the medical records of 75 consecutive cases supported with a LVAD (mean age of 39 years, 60 men, paracorporeal pulsatile-flow LVAD in 31, implantable centrifugal-flow in 18, and implantable axial-flow in 26) in our institution between December 2009 and June 2014. The incidence rate of CVAs was estimated as events per patient-year, and baseline characteristics (age, sex, etiologies of heart failure, comorbid diseases, and types of LVAD) were assessed to determine their contribution to the incidences of total, ischemic and hemorrhagic CVAs.

Results: During 113.7 patient-years of observation, a total of 59 CVA events (26 hemorrhagic and 33 ischemic) were identified in 31 cases, yielding an incidence rate of 0.52 events per patient-year. Univariate negative binomial regression (NBR) analysis demonstrated that patients with an axial-flow LVAD had significantly lower incidence of total CVAs [incidence rate ratio (IRR) 0.29, 95% confidence interval (CI) 0.10 - 0.88, p=0.03] and subsignificantly of both of ischemic (0.30, 0.05 - 1.69, p=0.17) and hemorrhagic CVAs (0.29, 0.08 - 1.02, p=0.05) than those with a paracorporeal LVAD (reference), whereas those with a centrifugal-flow LVAD did not. Patients with diabetes had a significantly higher incidence of total CVAs (IRR 2.39, 95% CI 1.03 - 5.57, p=0.04) and ischemic CVAs (4.01, 1.31 - 12.2, p=0.02) than those without diabetes but not of hemorrhagic CVAs (1.41, 0.54 - 3.66, p=0.48). Results of multivariate NBR analysis were similar with those of univariate analysis.

Conclusion: Among patients on LVAD support, CVA occurred at a rate of 0.52 events per patient-year. Axial-flow LVADs reduced the incidence of CVAs, regardless of ischemic or hemorrhagic subtype, compared with paracorporeal LVADs. Diabetes was associated with an increased risk of CVAs, but the influence was different between ischemic and hemorrhagic CVAs.