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heart transplantation has evolved into the gold standard treatment for patients with end - stage congestive heart failure . as outcomes of heart transplantation have improved ,
the number of patients waiting for heart transplantation has markedly increased , and the upper limit of the recipient 's age has been raised in some centers [ 2 - 4 ] . however , it has been suggested that advanced age is considered a relative contraindication for heart transplantation due to the high incidence of co - morbidities such as malignancies , hypertension , diabetes mellitus , and reduced life expectancy after heart transplantation . in addition , heart transplantation in elderly patients is still under debate because the shortage of donor hearts has been aggravated .
the aim of this study was to evaluate early- and mid - term results of heart transplantation in patients 60 years old when compared with those of heart transplantation in patients < 60 years old .
between march 1994 and december 2011 , 81 patients underwent heart transplantation in seoul national university hospital .
the mean age was 49.114.0 years ; 60 patients were younger than 60 years at the time of heart transplantation ( group y ) and 21 patients were 60 years or older ( group o ) .
dilated cardiomyopathy was the most common indication for heart transplantation ( n=42 , 51.9% ) .
two techniques for heart transplantation were used . in most patients ( 96.3% ) , the bicaval wythenshawe technique ( bicaval and single left atrial anastomoses )   was used .
the conventional lower and shumway technique   was used in 3 patients ( 3.7% ) who underwent transplantation in the early period .
the mean cardiopulmonary bypass ( cpb ) and donor heart ischemic times were 24177 and 15549 minutes , respectively .
the mean cpb time in group o was significantly longer than that in group y ( p=0.004 ) ( table 2 ) .
the patients underwent regular postoperative follow - up through the outpatient clinic at 3-month or 4-month intervals .
the patients were also contacted by telephone for confirmation of their condition if the last clinic visit was not conducted at the scheduled time .
follow - up was completed in all patients with a mean follow - up duration of 51.862.7 months . the standard maintenance immune suppression protocol for heart transplantation ( so - called " triple therapy " )
was used : ( 1 ) a calcineurin inhibitor such as cyclosporine or tacrolimus , ( 2 ) an antiproliferative agent such as azathioprine ( aza , imuran ) or mycophenolate mofetil ( mmf ) , and ( 3 ) corticosteroids such as prednisone or prednisolone .
cyclosporine , aza , and prednisolone were used in the early period until june 1999 . at that point ,
, the calcineurin inhibitor was changed from cyclosporine to tacrolimus with an addition of interleukin-2 .
intravenous methylprednisolone ( 500 mg ) was administered intraoperatively and followed by 3 doses ( 150 mg every 8 hours ) postoperatively .
prednisone was then given at a daily dose of 1 mg / kg ( per oral steroid ) and tapered over six months to 0.1 mg / kg per day .
the patients underwent endomyocardial biopsy weekly for 4 weeks after transplantation , every 4 weeks until the third month , and then every 3 months until the second year .
rejection severity was graded from 0 to 4 based on the international society for heart and lung transplantation ( ishlt ) grading system .
intravenous methylprednisolone ( 1 g / day for 3 days ) was given for grade 3a .
comparisons between the two groups were performed using the chi - squared or fisher 's exact test for categorical variables and the student 's t - test for continuous variables .
survival rates were estimated using the kaplan - meier method and comparisons between the 2 groups were performed using the log - rank test .
the cox proportional hazards model was adopted for analysis of risk factors for time related events .
the institutional review board of the seoul national university hospital approved this study ( snuh irb no .
between march 1994 and december 2011 , 81 patients underwent heart transplantation in seoul national university hospital .
the mean age was 49.114.0 years ; 60 patients were younger than 60 years at the time of heart transplantation ( group y ) and 21 patients were 60 years or older ( group o ) .
dilated cardiomyopathy was the most common indication for heart transplantation ( n=42 , 51.9% ) .
two techniques for heart transplantation were used . in most patients ( 96.3% ) , the bicaval wythenshawe technique ( bicaval and single left atrial anastomoses )   was used .
the conventional lower and shumway technique   was used in 3 patients ( 3.7% ) who underwent transplantation in the early period .
the mean cardiopulmonary bypass ( cpb ) and donor heart ischemic times were 24177 and 15549 minutes , respectively .
the mean cpb time in group o was significantly longer than that in group y ( p=0.004 ) ( table 2 ) .
the patients underwent regular postoperative follow - up through the outpatient clinic at 3-month or 4-month intervals .
the patients were also contacted by telephone for confirmation of their condition if the last clinic visit was not conducted at the scheduled time .
follow - up was completed in all patients with a mean follow - up duration of 51.862.7 months .
the standard maintenance immune suppression protocol for heart transplantation ( so - called " triple therapy " ) was used : ( 1 ) a calcineurin inhibitor such as cyclosporine or tacrolimus , ( 2 ) an antiproliferative agent such as azathioprine ( aza , imuran ) or mycophenolate mofetil ( mmf ) , and ( 3 ) corticosteroids such as prednisone or prednisolone .
cyclosporine , aza , and prednisolone were used in the early period until june 1999 . at that point ,
intravenous methylprednisolone ( 500 mg ) was administered intraoperatively and followed by 3 doses ( 150 mg every 8 hours ) postoperatively .
prednisone was then given at a daily dose of 1 mg / kg ( per oral steroid ) and tapered over six months to 0.1 mg / kg per day .
the patients underwent endomyocardial biopsy weekly for 4 weeks after transplantation , every 4 weeks until the third month , and then every 3 months until the second year .
rejection severity was graded from 0 to 4 based on the international society for heart and lung transplantation ( ishlt ) grading system .
intravenous methylprednisolone ( 1 g / day for 3 days ) was given for grade 3a .
comparisons between the two groups were performed using the chi - squared or fisher 's exact test for categorical variables and the student 's t - test for continuous variables .
survival rates were estimated using the kaplan - meier method and comparisons between the 2 groups were performed using the log - rank test .
the cox proportional hazards model was adopted for analysis of risk factors for time related events .
the institutional review board of the seoul national university hospital approved this study ( snuh irb no .
there were 4 early mortalities ( 30 days ) : 3 ( 5.0% ) in group y and 1 ( 4.8% ) in group o ( p>0.999 ) .
postoperative morbidities included renal failure requiring dialysis ( n=10 , 12.3% ) , bleeding reoperation ( n=8 , 9.9% ) , pneumonia ( n=10 , 12.3% ) , wound problems ( n=8 , 9.9% ) , and atrial fibrillation ( n=3 , 3.7% ) .
early mortalities or postoperative complications in the two groups did not differ ( table 3 ) .
the intensive care unit and hospital stays were also similar in the two groups . among 77 survivors , late mortality ( > 30 days ) occurred in 25 patients ( 32.5% ) .
one - year and 5-year survival rates were 84.6% and 67.9% in group y and 75.9% and 60.7% in group o , respectively .
there was no difference in overall survival between the 2 groups ( p=0.201 ) ( fig .
multivariate analysis revealed that age 60 years was not a significant risk factor for overall survival ; postoperative renal failure was the only significant risk factor for overall survival ( p=0.011 ) ( table 4 ) .
freedom from infection at 1 and 3 years was 72.5% and 67.8% in group y and 63.6% and 63.6% in group o , respectively ( p=0.586 ) ( fig .
2 ) . freedom from rejection ( ishlt grade 1b ) at 1 year was 73.9% in group o and 45.9% in group y , respectively ( p=0.026 ) ( fig .
there were 4 early mortalities ( 30 days ) : 3 ( 5.0% ) in group y and 1 ( 4.8% ) in group o ( p>0.999 ) .
postoperative morbidities included renal failure requiring dialysis ( n=10 , 12.3% ) , bleeding reoperation ( n=8 , 9.9% ) , pneumonia ( n=10 , 12.3% ) , wound problems ( n=8 , 9.9% ) , and atrial fibrillation ( n=3 , 3.7% ) .
early mortalities or postoperative complications in the two groups did not differ ( table 3 ) .
among 77 survivors , late mortality ( > 30 days ) occurred in 25 patients ( 32.5% ) .
one - year and 5-year survival rates were 84.6% and 67.9% in group y and 75.9% and 60.7% in group o , respectively .
there was no difference in overall survival between the 2 groups ( p=0.201 ) ( fig .
1 ) . multivariate analysis revealed that age 60 years was not a significant risk factor for overall survival ; postoperative renal failure was the only significant risk factor for overall survival ( p=0.011 ) ( table 4 ) .
freedom from infection at 1 and 3 years was 72.5% and 67.8% in group y and 63.6% and 63.6% in group o , respectively ( p=0.586 ) ( fig .
2 ) . freedom from rejection ( ishlt grade 1b ) at 1 year was 73.9% in group o and 45.9% in group y , respectively ( p=0.026 ) ( fig .
first , there were no significant differences in the early results and mid - term survival between the elderly patients ( 60 years ) and young patients ( < 60 years ) at the time of transplantation .
second , the elderly patients demonstrated a significantly higher freedom from rejection at 1 year .
advanced age has traditionally been considered a relative contraindication for heart transplantation [ 5,6,11 - 13 ] . according to the 2011 report from the registry of the ishlt ,
increasing recipient age remains an independent risk factor that adversely affects survival after heart transplantation . because of the critical shortage of donor organs , selection of candidates for transplantation
is based on the potential for maximal benefit in terms of functional recovery and length of survival .
in addition , advanced age is associated with shorter life expectancy and higher incidence of comorbidities such as hypertension and diabetes . because of the rapid increase in the number of elderly patients , the number of candidates for transplantation older than 60 years has steadily increased .
however , the recipient age limit for heart transplantation is still a matter of debate .
several studies have shown that heart transplantation in elderly patients could be performed successfully with acceptable morbidity and mortality and enhanced long - term survival , when compared with those of younger patients [ 2 - 4,16 ] .
recent advancements in postoperative care after heart transplantation , including the infection control protocols and immune suppression regimen , may have enabled that improvement . in the present study ,
the early mortality rate was low and there were no differences in 1- or 5-year survival rates of groups y and o. previous studies have demonstrated that the incidence of infection was higher in older patient groups . in the present study , however , freedom from infection until postoperative 3 years was similar in the 2 groups . this seems to be due to improvements in the medications for infection control and immune suppression .
previous studies have also demonstrated that the incidence of acute cellular rejection was lower in older patients , and the present study also showed a similar result .
our immune suppression strategies have changed over time ; however , the same strategies were used in the two groups . an age - related decrease in immune reactivity and t - cell function
might be responsible for this effect . in multivariable analysis , recipient age at the time of transplantation
was not a risk factor for overall survival , but instead postoperative renal failure was the only significant risk factor .
first , this study was a nonrandomized , retrospective , observational study in a single institution .
third , the follow - up duration was different between the 2 groups because we began to perform heart transplantation in the elderly patients only recently .
the mortality and morbidity after heart transplantation did not increase significantly in the elderly patients ( 60 years ) , when compared with the younger patients ( < 60 years ) .
heart transplantation might also be considered to be a treatment option for elderly heart failure patients , although careful patient selection criteria should be applied considering donor shortage in the current era .
backgroundheart transplantation in elderly patients has raised concerns because of co - morbidities and limited life expectancy in the era of donor shortage . 
 we examined the outcomes after heart transplantation in elderly patients.materials and methodsfrom march 1994 to december 2011 , 81 patients ( male : female=64:17 , 49.114.0 years ) underwent heart transplantation . 
 the outcomes after heart transplantation in the younger patients ( < 60 years ; group y , n=60 ) were compared with those in the elderly patients ( 60 years ; group o , n=21 ) . 
 the follow - up duration was 51.862.7 months.resultsearly mortality ( 30 days ) occurred in 5.0% ( 3/60 ) and 4.8% ( 1/21 ) of groups y and o , respectively ( p>0.999 ) . 
 there were no differences in overall survival between the two groups ( p=0.201 ) . 
 freedom from rejection was higher in group o than in group y ( p=0.026 ) . 
 multivariable analysis revealed that age 60 years was not a significant risk factor for long - term survival ; postoperative renal failure was the only significant risk factor for long - term survival ( p=0.011).conclusionearly and mid - term results of heart transplantation in elderly patients were similar to those in younger patients .