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.