Spanish experience with heart transplants from controlled donation after the circulatory determination of death using thoraco-abdominal normothermic regional perfusion and cold storage.

Heart transplantation from controlled donation after the circulatory determination of death (cDCDD) may help to increase the availability of hearts for transplantation. During 2020, four heart transplants were performed at three different Spanish hospitals based on the use of thoraco-abdominal normothermic regional perfusion (TA-NRP) followed by cold storage (CS). All donors were young adults <45 years. The functional warms ischemic time ranged from 8 to 16 minutes. In all cases, the heart recovered sinus rhythm within 1 minute of TA-NRP. TA-NRP was weaned off or decreased <1L within 25 minutes. No recipient required mechanical support after transplantation and all were immediately extubated and discharged home (median hospital stay: 21 days) with an excellent outcome. Four livers, eight kidneys, and two pancreata were also recovered and transplanted. All abdominal grafts recipients experienced an excellent outcome. The use of TA-NRP makes heart transplantation feasible and allows assessing heart function before organ procurement without any negative impact on the preservation of abdominal organs. The use of TA-NRP in cDCDD heart donors in conjunction with cold storage following retrieval can eliminate the need to use ex situ machine perfusion devices, making cDCDD heart transplantation economically possible in other countries.

Gender differences in heart transplantation: Twenty-five year trends in the nationwide Spanish heart transplant registry.

The study of gender differences may lead into improvement in patient care. We have aimed to identify the gender differences in heart transplantation (HT) of adult HT recipients in Spain and their evolution in a study covering the years 1993-2017 in which 6740 HT (20.6% in women) were performed. HT indication rate per million inhabitants was lower in women, remaining basically unchanged during the 25-year study period. HT rate was higher in men, although this decreased over the 25-year study period. Type of heart disease differed in men versus women (p < .001): ischemic heart disease 47.6% versus 22.5%, dilated cardiomyopathy 41.3% versus 34.6%, or other 36% versus 17.8%, respectively. Men were more frequently diabetics (18% vs. 13.1% p < .001), hypertensives (33.1% vs. 24% p < .001), and smokers (21.7% vs. 12.9% p < .001), respectively. Women had more pre-HT malignancies (7.1% vs. 2.8% p < .001), and their clinical status was worse at HT due to renal function and mechanical ventilation. Adjusted survival (p = .198) and most of the mortality-related variables were similar in men and women. Death occurred more frequently in women due to rejection (7.9% vs. 5.1% p < .001) and primary failure (18.2% vs. 12.5% p < .001) and in men due to malignancies (15.1% vs. 6.6% p < .001).

Review of the allocation criteria for heart transplant in Spain in 2023. SEC-Heart Failure Association/ONT/SECCE consensus document.

Heart transplant (HT) remains the best therapeutic option for patients with advanced heart failure (HF). The allocation criteria aim to guarantee equitable access to HT and prioritize patients with a worse clinical status. To review the HT allocation criteria, the Heart Failure Association of the Spanish Society of Cardiology (HFA-SEC), the Spanish Society of Cardiovascular and Endovascular Surgery (SECCE) and the National Transplant Organization (ONT), organized a consensus conference involving adult and pediatric cardiologists, adult and pediatric cardiac surgeons, transplant coordinators from all over Spain, and physicians and nurses from the ONT. The aims of the consensus conference were as follows: a) to analyze the organization and management of patients with advanced HF and cardiogenic shock in Spain; b) to critically review heart allocation and priority criteria in other transplant organizations; c) to analyze the outcomes of patients listed and transplanted before and after the modification of the heart allocation criteria in 2017; and d) to propose new heart allocation criteria in Spain after an analysis of the available evidence and multidisciplinary discussion. In this article, by the HFA-SEC, SECCE and the ONT we present the results of the analysis performed in the consensus conference and the rationale for the new heart allocation criteria in Spain.

The international experience of in-situ recovery of the DCD heart: a multicentre retrospective observational study.

Background: Heart transplantation is an effective treatment offering the best recovery in both quality and quantity of life in those affected by refractory, severe heart failure. However, transplantation is limited by donor organ availability. The reintroduction of heart donation after the circulatory determination of death (DCD) in 2014 offered an uplift in transplant activity by 30%. Thoraco-abdominal normothermic regional perfusion (taNRP) enables in-situ reperfusion of the DCD heart. The objective of this paper is to assess the clinical outcomes of DCD donor hearts recovered and transplanted from donors undergoing taNRP. Method: This was a multicentre retrospective observational study. Outcomes included functional warm ischaemic time, use of mechanical support immediately following transplantation, perioperative and long-term actuarial survival and incidence of acute rejection requiring treatment. 157 taNRP DCD heart transplants, performed between February 2, 2015, and July 29, 2022, have been included from 15 major transplant centres worldwide including the UK, Spain, the USA and Belgium. 673 donations after the neurological determination of death (DBD) heart transplantations from the same centres were used as a comparison group for survival. Findings: taNRP resulted in a 23% increase in heart transplantation activity. Survival was similar in the taNRP group when compared to DBD. 30-day survival was 96.8% ([92.5%-98.6%] 95% CI, n = 156), 1-year survival was 93.2% ([87.7%-96.3%] 95% CI, n = 72) and 5-year survival was 84.3% ([69.6%-92.2%] 95% CI, n = 13). Interpretation: Our study suggests that taNRP provides a significant boost to heart transplantation activity. The survival rates of taNRP are comparable to those obtained for DBD transplantation in this study. The similar survival may in part be related to a short warm ischaemic time or through a possible selection bias of younger donors, this being an uncontrolled observational study. Therefore, our study suggests that taNRP offers an effective method of organ preservation and procurement. This early success of the technique warrants further investigation and use. Funding: None of the authors have a financial relationship with a commercial entity that has an interest in the subject.

Best practices during COVID-19 pandemic in solid organ transplant programs in Spain.

Clinical management of transplant patients abruptly changed during the first months of COVID-19 pandemic (March to May 2020). The new situation led to very significant challenges, such as new forms of relationship between healthcare providers and patients and other professionals, design of protocols to prevent disease transmission and treatment of infected patients, management of waiting lists and of transplant programs during state/city lockdown, relevant reduction of medical training and educational activities, halt or delays of ongoing research, etc. The two main objectives of the current report are: 1) to promote a project of best practices in transplantation taking advantage of the knowledge and experience acquired by professionals during the evolving situation of the COVID-19 pandemic, both in performing their usual care activity, as well as in the adjustments taken to adapt to the clinical context, and 2) to create a document that collects these best practices, thus allowing the creation of a useful compendium for the exchange of knowledge between different Transplant Units. The scientific committee and expert panel finally standardized 30 best practices, including for the pretransplant period (n = 9), peritransplant period (n = 7), postransplant period (n = 8) and training and communication (n = 6). Many aspects of hospitals and units networking, telematic approaches, patient care, value-based medicine, hospitalization, and outpatient visit strategies, training for novelties and communication skills were covered. Massive vaccination has greatly improved the outcomes of the pandemic, with a decrease in severe cases requiring intensive care and a reduction in mortality. However, suboptimal responses to vaccines have been observed in transplant recipients, and health care strategic plans are necessary in these vulnerable populations. The best practices contained in this expert panel report may aid to their broader implementation.

Influence of Gender in Advanced Heart Failure Therapies and Outcome Following Transplantation.

Biological differences between males and females change the course of different diseases and affect therapeutic measures' responses. Heart failure is not an exception to these differences. Women account for a minority of patients on the waiting list for heart transplantation or other advanced heart failure therapies. The reason for this under-representation is unknown. Men have a worse cardiovascular risk profile and suffer more often from ischemic heart disease. Conversely, transplanted women are younger and more frequently have non-ischemic cardiac disorders. Women's poorer survival on the waiting list for heart transplantation has been previously described, but this trend has been corrected in recent years. The use of ventricular assist devices in women is progressively increasing, with comparable results than in men. The indication rate for a heart transplant in women (number of women on the waiting list for millions of habitants) has remained unchanged over the past 25 years. Long-term results of heart transplants are equal for both men and women. We have analyzed the data of a national registry of heart transplant patients to look for possible future directions for a more in-depth study of sex differences in this area. We have analyzed 1-year outcomes of heart transplant recipients. We found similar results in men and women and no sex-related interactions with any of the factors related to survival or differences in death causes between men and women. We should keep trying to approach sex differences in prospective studies to confirm if they deserve a different approach, which is not supported by current evidence.

Risk factors associated with moderate-to-severe renal dysfunction among heart transplant patients: results from the CAPRI study.

The longer survival of patients with heart transplantation (HT) favors calcineurin inhibitor-related chronic kidney disease (CKD). It behoves to identify risk factors. At 14 Spanish centers, data on 1062 adult patients with HT (age 59.2 ± 12.3 yr, 82.5% men) were collected at routine follow-up examinations. Glomerular filtration rate, GFR, was estimated using the four-variable MDRD equation, and moderate-or-severe renal dysfunction (MSRD) was defined as K/DOQI stage 3 CKD or worse. Time since transplant ranged from one month to 22 yr (mean 6.7 yr). At assessment, 26.6% of patients were diabetic and 63.9% hypertensive; 53.9% were taking cyclosporine and 33.1% tacrolimus; and 61.4% had MSRD. Among patients on cyclosporine or tacrolimus at assessment, multivariate logistic regression identified male sex (OR 0.44), pre- and post-HT creatinine (2.73 and 3.13 per mg/dL), age at transplant (1.06 per yr), time since transplant (1.05 per yr), and tacrolimus (0.65) as independent positive or negative predictors of MSRD. It is concluded that female sex, pre- and one-month post-HT serum creatinine, age at transplant, time since transplant, and immunosuppression with cyclosporine rather than tacrolimus may all be risk factors for development of CKD ≥ stage 3 by patients with HT.

Prevalence and severity of renal dysfunction among 1062 heart transplant patients according to criteria based on serum creatinine and estimated glomerular filtration rate: results from the CAPRI study.

Chronic kidney disease (CKD) is staged on the basis of glomerular filtration rate; generally, the MDRD study estimate, eGFR, is used. Renal dysfunction (RD) in heart transplant (HT) patients is often evaluated solely in terms of serum creatinine (SCr). In a cross-sectional, 14-center study of 1062 stable adult HT patients aged 59.1±12.5 yr (82.3% men), RD was graded as absent-or-mild (AoM), moderate, or severe (this last including dialysis and kidney graft) by two classifications: SCr-RD (SCr cutoffs 1.6 and 2.5 mg/dL) and eGFR-RD (eGFR cutoffs 60 and 30 mL/min/1.73 m2). SCr-RD was AoM in 68.5% of patients, moderate in 24.9%, and severe in 6.7%; eGFR-RD, AoM in 38.6%, moderate in 52.2%, severe in 9.2%. Among patients evaluated <2.7, 2.7-6.2, 6.2-9.5 and >9.5 yr post-HT (the periods defined by time-since-transplant quartiles), AoM/moderate/severe RD prevalences were <2.7, SCr-RD 74/21/5%, eGFR-RD 47/47/6%; 2.7-6.2, SCr-RD 73/22/5%, eGFR-RD 37/56/7%; 6.2-9.5, SCr-RD 69/24/7%, eGFR-RD 37/54/9%; >9.5, SCr-RD 58/32/10%, eGFR-RD 32/52/16%. The prevalence of severe RD increases with time since transplant. If the usual CKD stages are appropriate for HT patients, the need for less nephrotoxic immunosuppressants and other renoprotective measures is greater than is suggested by direct SCr-based grading, which should be abandoned as excessively insensitive.

Conversion From Immediate-Release Tacrolimus to Prolonged-Release Tacrolimus in Stable Heart Transplant Patients: A Retrospective Study.

BACKGROUND: Lifelong adherence with post-transplant immunosuppression is challenging, with nonadherence associated with greater acute rejection (AR) risk. METHODS: This retrospective study evaluated conversion from immediate-release tacrolimus (IRT) to prolonged-release tacrolimus (PRT), between January 2008 and December 2012 in stable adult heart transplant recipients. Cumulative incidence rate (IR) of AR and infection pre- and postconversion, safety, tacrolimus dose and trough levels, concomitant immunosuppression, and PRT discontinuation were analyzed (intention-to-treat population). RESULTS: Overall, 467 patients (mean age, 59.3 [SD, 13.3] years) converted to PRT at 5.1 (SD, 4.9) years post transplant and were followed for 3.4 (SD, 1.5) years. During the 6 months post conversion, 5 patients (1.1%; 95% CI, 0.35%-2.48%) had an AR episode and IR was 2.2/100 patient-years (95% CI, 0.91-5.26). Incidence of rejection preconversion varied by time from transplant to conversion. Infection IR was similar post- and preconversion (9.2/100 patient-years [95% CI, 7.4-11.3] vs 10.6/100 patient-years [95% CI, 8.8-12.3], respectively; P = .20). Safety variables remained similar post conversion. The IR of mortality/graft loss was 2.3/100 patient-years (95% CI, 1.7-3.1). CONCLUSIONS: Conversion from IRT to PRT in heart transplant recipients in Spain was associated with no new safety concerns and appropriate immunosuppressive effectiveness.

Increased major bleeding complications related to triple antithrombotic therapy usage in patients with atrial fibrillation undergoing percutaneous coronary artery stenting.

BACKGROUND: The optimal antithrombotic therapy strategy for atrial fibrillation (AF) patients who undergo percutaneous coronary intervention with stent implantation (PCI-S) is unknown. We assessed the safety of antithrombotic therapy strategies in AF patients with indication for oral anticoagulation (OAC) undergoing PCI-S. METHODS: We studied consecutive AF patients with indication for OAC who underwent PCI-S. We compared patients that received triple antithrombotic therapy (TT) [aspirin, clopidogrel, and coumadin] against other regimes (non-TT) after PCI-S. The primary end point was defined as the occurrence of major bleeding complications that were termed as early major bleeding (EMB) [< or = 48 h] or late major bleeding (LMB) [> 48 h]. Clinical follow-up was performed, and complications were recorded. RESULTS: We studied 104 patients (mean age +/- SD, 72 +/- 8 years; 70% men); TT was used in 51 patients (49%). TT was associated with a higher incidence of LMB (21.6% vs non-TT, 3.8%; p = 0.006) but not of EMB (5.8% vs non-TT, 11.3%; p = 0.33). In multivariate analyses, glycoprotein (GP) IIb/IIIa inhibitor use (hazard ratio [HR], 13.5; 95% confidence interval [CI], 1.7 to 108.3; p = 0.014) and PCI-S of three vessels or left main artery disease (HR, 7.9; 95% CI, 1.6 to 39.2; p = 0.01) were independent predictors for EMB. TT use (HR, 7.1; 95% CI, 1.5 to 32.4; p = 0.012), the occurrence of EMB (HR, 6.7; 95% CI, 1.8 to 25.3; p = 0.005), and baseline anemia (HR, 3.8; 95% CI, 1.2 to 12.5; p = 0.027) were independent predictors for LMB. No differences in major cardiovascular events were observed in patients treated with TT vs non-TT (25.5% vs 21.0%; p = 0.53). CONCLUSION: A high rate of major bleeding is observed in AF patients with indication for OAC undergoing PCI-S who receive TT. GP IIb/IIIa inhibitor use and multivessel/left main artery disease during PCI-S were independent predictors for EMB, while TT use, occurrence of EMB, and baseline anemia were independent predictors for LMB.

A new simple method to assess global left ventricular systolic function based on the sum of regional myocardial velocities.

The relations between left ventricular (LV) function and global tissue Doppler velocity, strain rate, and strain were assessed in 99 studies. Significant correlations were found between the LV ejection fraction and global tissue Doppler velocity, strain, and strain rate (r = 0.50, r = 0.63, and r = 0.46, respectively, all p <0.001), suggesting that this global assessment may be useful in evaluating LV function.

Prognostic value of exercise echocardiography in patients with diabetes mellitus and known or suspected coronary artery disease.

To assess the prognostic value of exercise echocardiography in subjects who had diabetes, we studied 214 patients who had 28 hard cardiac events (cardiac death in 15, myocardial infarction in 13) during a follow-up of 44 +/- 16 months. Independent risk factors for predicting cardiac events were insulin therapy (odds ratio 2.313), peak left ventricular ejection fraction (odds ratio 0.973), and ischemia detected by exercise echocardiography (odds ratio 2.513).

Mineralocorticoid receptor antagonists modulate galectin-3 and interleukin-33/ST2 signaling in left ventricular systolic dysfunction after acute myocardial infarction.

OBJECTIVES: This study aimed to evaluate the specific role of the 2 available mineralocorticoid receptor antagonists (MRAs), eplerenone and spironolactone, on the modulation of galectin-3 (Gal-3) and interleukin (IL)-33/ST2 signaling in an experimental model of left ventricular systolic dysfunction after acute myocardial infarction (MI). BACKGROUND: The molecular mechanisms of benefits of MRAs in patients with left ventricular systolic dysfunction after MI not well understood. METHODS: MI and left ventricular systolic dysfunction were induced by permanent ligation of the anterior coronary artery in 45 male Wistar rats, randomly assigned to no therapy (MI group, n = 15) or to receive MRAs (100 mg/kg/day) for 4 weeks; either eplerenone (n = 15) or spironolactone (n = 15) was used. A sham group was used as a control (n = 8). Elements of the pathway for Gal-3 including transforming growth factor (TGF)-ß and SMAD3, as well as that for IL-33/ST2 (including IL-33 and soluble ST2 [sST2]) were analyzed in the infarcted and noninfarcted myocardium by quantitative real-time reverse transcription polymerase chain reaction. Expression of markers of fibrosis (collagen types I and III, tissue inhibitor of metalloproteinase-1) and inflammation (IL-6, tumor necrosis factor-α, monocyte chemotactic protein-1) was also examined. RESULTS: In the infarcted myocardium, compared with sham animals, the MI group had higher concentrations of Gal-3, TGF-ß, SMAD3, IL-33, and sST2, as well as higher concentrations of markers of fibrosis and inflammation. Treatment with MRAs down-regulated Gal-3, TGF-ß, and SMAD3 and enhanced IL-33/ST2 signaling with lower expression of sST2; protective IL-33 up-regulation was unaffected by MRAs. Modulation of Gal-3 and IL-33/ST2 signaling induced by MRAs correlated with lower expression levels of fibrosis and inflammatory markers. No differences were found between eplerenone and spironolactone. In the noninfarcted myocardium, compared with sham animals, the MI group exhibited a higher expression of Gal-3 and IL-33, but no signs of inflammation or fibrosis were observed; in the presence of MRAs, IL-33 expression was significantly up-regulated, but Gal-3 was unaffected. CONCLUSIONS: MRAs play a pivotal role in the Gal-3 and IL-33/ST2 modulation in post-MI cardiac remodeling.

Exercise echocardiography with addition of atropine.

Exercise echocardiography with the addition of atropine was performed in 31 patients who had a very small probability of achieving submaximal heart rate. Conclusive tests were obtained in 77% of the patients with this protocol.

Comparison of exercise echocardiography to exercise electrocardiographic testing added to echocardiography at rest for risk stratification after uncomplicated acute myocardial infarction.

Recommendations for risk assessment after acute myocardial infarction (AMI) include electrocardiographic (ECG) exercise testing. We hypothesized that a more sensitive technique, exercise echocardiography (EE), would refer a greater number of patients to invasive procedures. Therefore, we compared a strategy based on EE with a strategy based on ECG exercise testing for patients with uncomplicated AMI. A series of 164 patients referred for exercise testing after AMI were randomized to treadmill EE (strategy 2) or baseline echocardiography and ECG treadmill exercise testing (strategy 1). Ischemic response was more frequently detected with strategy 2 (59% vs 27%, p <0.001), and consequently angiography and revascularization procedures were more commonly performed (59 vs 32 procedures, p <0.01 and 46 vs 19 procedures, p <0.001, respectively). Fourteen percent and 15% of patients experienced soft events (unstable angina, heart failure, or late revascularization) after strategy 1 and strategy 2, respectively (p = NS); 6% and 9% of patients had hard events (nonfatal AMI or cardiovascular death) at follow-up (p = NS). In conclusion, a strategy based on EE detected more patients with ischemia; therefore, more patients were submitted to coronary angiography and revascularization procedures. No differences were detected in cardiac events when we compared this strategy with the less expensive ECG exercise testing after uncomplicated AMI.

Relation of ischemia-modified albumin (IMA) levels following elective angioplasty for stable angina pectoris to duration of balloon-induced myocardial ischemia.

The results in this study confirm and expand previous reports that ischemia-modified albumin (IMA) is an early marker of ischemia in the setting of percutaneous coronary intervention (PCI). We observed that IMA levels are related to the number of inflations, inflation pressure, and duration of inflations. It is therefore likely that IMA reflects the magnitude and duration of ischemia induced during PCI.

Comparison of ischemia-modified albumin levels in patients undergoing percutaneous coronary intervention for unstable angina pectoris with versus without coronary collaterals.

This study compared ischemia-modified albumin levels, a marker of ischemia in patients undergoing percutaneous coronary intervention. Ischemia-modified albumin levels were significantly lower in patients with collateral circulation compared with those without collateral circulation.

Comparison of peak and postexercise treadmill echocardiography with the use of continuous harmonic imaging acquisition.

OBJECTIVES: We sought to compare the feasibility and accuracy of peak and postexercise treadmill echocardiography with the use of continuous harmonic imaging capture. BACKGROUND: Previous work has demonstrated the superiority of peak exercise echocardiography (EE) as compared with post-EE for the diagnosis of coronary artery disease (CAD). However, most of these studies used fundamental imaging and view-per-view acquisition systems. Technical advantages in stress echocardiography include harmonic imaging and continuous imaging capture. METHODS: The study group included 650 patients (423 men; 60 +/- 12 years) who were submitted to peak and postexercise treadmill echocardiography. RESULTS: Postexercise images were acquired within 55 seconds after exercise (28 +/- 10). The number of segments visualized in each view were similar at peak and post-EE except for the parasternal short-axis view, which was better qualified at postexercise. For analysis of diagnostic capability we included 312 patients: 195 were included on the basis of having had an EE and a coronary angiography, whereas 117 patients with pretest probability of CAD < 10% who had atypical chest pain or were asymptomatic were also included and considered as having no CAD. CAD (>/=50% stenosis) was confirmed in 159 patients. Positive EE was defined as ischemia or necrosis. Sensitivity for CAD was higher with peak imaging (92% vs 77%, P <.001), with similar specificity (78% vs 87%, P = not significant) and accuracy (85% vs 82%, P = not significant). CONCLUSION: Peak treadmill EE is technically feasible and has higher sensitivity for CAD than posttreadmill EE. Therefore, in the clinical setting, peak EE should be performed for diagnostic purposes.

[Real time myocardial contrast echocardiography to predict left ventricular wall motion recovery after reperfused acute myocardial infarction]. / Ecocardiografía de perfusión miocárdica en tiempo real para la predicción de la recuperación de la función ventricular después del infarto agudo de miocardio reperfundido.

INTRODUCTION AND OBJECTIVES: Real time myocardial contrast echocardiography (RTMCE) is a recently developed method. We sought to determine: a) whether RTMCE predicts recovery of left ventricular function after acute myocardial infarction (AMI), and b) whether data obtained with this method are comparable to those obtained with 99mTc-sestamibi single photon emission computed tomography (SPECT) and magnetic resonance. PATIENTS AND METHOD: We studied 85 patients with AMI who underwent angioplasty. RTMCE was performed 7 (4) days after AMI. Two-dimensional echocardiography was performed at the time of the RTMCE study and at follow-up (10 [4] weeks). SPECT and magnetic resonance were performed after AMI in 18 and 32 patients, respectively. RESULTS: Follow-up two-dimensional echocardiography results were available for 82 patients, who were subdivided into 2 groups: recovery (n=49) and no recovery (n=33). Regional (AMI-related) wall motion score index improved from 1.75 (0.49) to 1.32 (0.36) (P< .001) in the recovery group, and worsened from 1.85 (0.39) to 1.95 (0.36) in the no recovery group (P< .001). RTMCE perfusion score was 0.8 (0.3) in the recovery group, and 0.6 (0.4) in the no recovery group (P< .001). Concordance between RTMCE and SPECT in a segmental analysis was 78% (P< .001; kappa=0.49), whereas concordance between RTMCE and hyperenhancement with delayed contrast magnetic resonance findings was 70% (P< .001; kappa =0.35). Independent predictors of recovery were peak creatine kinase (OR=1.4 per 1000 UI; 95% CI, 1.0-1.9; P< .05) and RTMCE score (OR=8.8; 95% CI, 1.9-39.3; P< .01). A RTMCE score > or = 0.60 had a positive predictive value of 73% and a negative predictive value of 69% (P< .001; area under the curve 0.70). CONCLUSION: RTMCE showed a modest predictive value for recovery of left ventricular function after reperfused AMI.

Optical coherence tomography and highly sensitivity troponin T for evaluating cardiac allograft vasculopathy.

Cardiac allograft vasculopathy (CAV) is a major impediment to long-term graft survival after heart transplantation. Intravascular ultrasound (IVUS) is more sensitive than coronary angiography for diagnosis, but the identification of specific plaque components or plaque composition is limited. In addition, there is an evident need for other noninvasive tools for diagnosing CAV. The aim of this study was to assess the utility of 2 new techniques for evaluating CAV: optical coherence tomography (OCT), and new high-sensitivity troponin T (hsTnT) assays. In 21 heart transplantation patients, coronary arteriography with IVUS and OCT were performed. Maximal intimal thickness (MIT) and luminal area at the most severe site were measured using the 2 techniques. Immediately before cardiac catheterization, blood samples were obtained and hsTnT levels measured. The evaluation of CAV by OCT showed a good correlation with IVUS measurements, with a mean difference in MIT of 0.0033 (95% confidence interval -0.049 to 0.043), taking advantage of lower interobserver variability (r = 0.94 for OCT vs r = 0.78 for IVUS) and better plaque characterization. When independent predictors of MIT were assessed in a multiple linear regression model, time after transplantation (ß = 0.488, p = 0.004) and hsTnT (ß = 0.392, p = 0.011) were the only independent predictors of MIT (R(2) = 0.591). In conclusion, this study is the first to evaluate 2 new techniques, OCT and hsTnT, in the challenging setting of CAV. The findings suggest that OCT provides lower interobserver variability and better plaque characterization than IVUS. Also, hsTnT could become a useful tool for ruling out CAV.