Data related to the characteristics of recipients, donors, surgical procedures, immunosuppression, and outcomes of all procedures are collected in a pre-established, Excel-based electronic database that can be accessed online. Updating this registry at least once per year is mandatory for participating centers. The Spanish Heart Transplant Registry is anonymized for patients, has been approved by an ethics committee, and is registered by the Spanish Society of Cardiology with the Spanish Ministry of Health as outlined in the Organic Law on Data Protection. The database is the property of the Spanish Society of Cardiology. Database maintenance, quality assurance, and statistical analysis are performed by an external contract research organization. The only significant change to the current database is related to the cutoff age for defining pediatric transplants, which is now 18 years, in line with the change made by the Spanish National Transplant Organization and is aimed at standardizing our data with those of international registries.

Currently, 19 centers have an active heart transplant program (table 1). Of these, 2 perform pediatric transplants alone (which is also performed in 4 other centers with an adult program) and 2 centers are equipped to perform cardiopulmonary transplants. The types of transplants performed in 2020 and in the entire series are summarized in table 2. With 278 transplants performed in 2020 (10.4% in recipients younger than 18 years and 26.9% in those older than 60 years), the Spanish Heart Transplant Registry includes 9060 procedures (figure 1). The outcomes from 2020 are compared with those from the previous decade segmented into 3-year periods (2011-2013, 2014-2016, and 2017-2019). The changes over time in the percentages of urgent transplants, the type of pretransplant circulatory support, and donor age were analyzed by year.

Figure 1.

Annual number of transplants (1984-2020); total and by age group.

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Continuous variables are expressed as mean±standard deviation, whereas categorical variables are expressed as percentages. Differences among time periods were analyzed using a nonparametric test for temporal trends (Kendall τ) for categorical variables and ANOVA (analysis of variance) with polynomial fit for continuous variables. Survival curves were calculated using the Kaplan-Meier test and were compared using a log-rank test. P <.05 was considered statistically significant.

In total, 278 transplants were performed in 2020, 7.3% less than in the previous year. The fall in the number of transplants was largely due to a decrease in April (figure 2). Recipient characteristics in 2020 and in the previous decade are summarized in table 3. At the time of transplantation, 10.2% of recipients were younger than 18 years and 26.9% were older than 60 years. The overall mean age was 48.7 years, similar to that of the previous decade; 33.1% were women. Almost one-third of the procedures were performed for heart diseases with etiologies other than ischemic or nonischemic dilated cardiomyopathy and in patients with previous cardiac surgery. In total, 39% of procedures were urgent (table 3); these procedures were largely performed with circulatory support via ventricular assist devices (figure 3). The percentage of urgent transplants has returned to the levels recorded at the start of the decade (about 38%), after a period (2013 and 2018) when it almost reached 50% (figure 4). In the last decade, there were no significant changes in the main characteristics of recipients, except an increase in the percentage of patients with previous cardiac surgery and a change in the type of pretransplant circulatory support, with the almost complete disappearance of the balloon pump and an increase in ventricular assist devices, mainly continuous flow (figure 3).

Figure 2.

Number of transplants per month in 2019 and 2020.

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Figure 3.

Distribution of the type of pretransplant circulatory support by year (2011-2020). ECMO, extracorporeal membrane oxygenation; VAD, ventricular assist device.

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Figure 4.

Annual percentage of urgent transplants in the total population (2011-2020).

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The characteristics of the donors and surgical procedures are summarized in table 4. Once again, a high percentage of transplants involved donors older than 45 years, which represented almost half of the patients. Nonetheless, after a peak in 2017, the subsequent years showed a slight decreasing tendency in the percentage of older donors (figure 5). As in previous years, the trends show a high percentage of transplants involving donors who had a preprocedural cardiac arrest or who died of stroke.

Figure 5.

Annual changes in donor age and in the percentages of donors older than 45 years (2011-2020). 95%CI, 95% confidence interval.

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The mean ischemia time has tended to fall in the last decade due to an increase in procedures with short ischemia times (≤ 120minutes) and a decrease in interventions with moderately long times (180-240minutes). In 2020, 4 of every 5 transplants were performed with a bicaval technique.

Induction immunosuppression in 2020 was in line with that observed in the previous 3-year period (2017-2019; table 5). The use of cyclosporin was very low (about 5%) and almost entirely limited to patients with adverse reactions to tacrolimus. Likewise, the use of azathioprine was barely recorded in the last decade. More than 80% of patients received antibody-based pretransplant induction therapy, mainly basiliximab.

In the last decade, survival was about 80% in the first posttransplant year and was more than 70% at 5 years, which was significantly higher than that recorded in the entire previous series (figure 6A). From the last decade, the most recent 3-year period (2017-2019) showed significantly higher survival vs the 2011 to 2013 period and nonsignificantly higher survival vs the 2014 to 2016 period (figure 6B). The 1-year survival rates in the 2011 to 2013, 2014 to 2016, and 2017 to 2019 periods were 77.7%, 78.9%, and 82.0%, respectively. As in previous years, the main univariable predictors of mortality were recipient age and urgent transplant, largely due to the higher mortality of recipients who received circulatory support with extracorporeal membrane oxygenation (table 6).

Figure 6.

A: comparison of survival curves between the 2011 to 2020 and 1984 to 2010 periods. B: comparison of survival curves in the 2011 to 2019 period by 3-year period.

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In the first 5 posttransplant years, almost half of deaths were due to primary graft failure or infection (figure 7), with primary graft failure concentrated in the first posttransplant month and infection in the remainder of the first year. Acute graft rejection was a major cause of death between the first and fifth post-transplant year (16.4%), only surpassed by combined sudden cardiac death/graft vascular disease (25.4%) and cancer (20.0%). These trends are similar to those recorded in the most recent registry analyses.

Figure 7.

Main causes of death according to time since transplantation in the 2011 to 2020 period.

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The trends in the posttransplant causes of death were analyzed only for those occurring in the first year, because complete information was available from this period for all patients (figure 8). The last decade showed a nonsignificant tendency for a decrease in primary graft failure as the cause of death, particularly since 2013, with infection and rejection maintained. Death due to rejection fell by almost half in the 2017 to 2019 period vs the previous 3-year period, although the difference was not significant due to the small number of events.

Figure 8.

Changes over time in the main causes of death in the first post-transplant year in the 2011 to 2020 period by 3-year period.

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