Six-year experience with cardiac surgery in adults with congenital heart disease

Summary

Background.
Increasing number of adults with congenital heart disease (ACHD) require reoperation or primary repair.

The aim.
To define risk and outcome of operations of ACHD performed in adult cardiac surgery.

Methods:
Between 2005-2010 we operated on 459 ACHD, aged 40,4±15 years. Operations of ACHD represented 9,5 % of 4854 cardiac operations in our department.

Results:
The 30-days mortality was 1,1 %, hospital mortality was 1,52 %, long-term mortality among discharged patients was 1,3 %. Reoperations after surgery in childhood represented 39 %, repeated reoperations 9 %, operations of 3 or 4 valves 2,6 %. Robotic surgery or minithoracotomy was performed in 9 %. Pulmonary hypertension was present in 11,3 %, NYHA III-IV in 30 %. The risk factors of mortality were: NYHA class III-IV (p<0,001), cyanosis (p<0,001), severe systolic dysfunction of left (p= 0,006) or right ventricle (p <0,001).We did not confirm increased risk in older patients, women, pulmonary hypertension, reoperations and operations of 3-4 valves.

Conclusion:
Excellent surgical results among older adults with CHD were achieved by the co-operation of pediatric cardiac surgeon within the experienced center for adult cardiac surgery. The highest risk was found in patients with NYHA class III-IV, cyanosis and ventricular dysfunction.

Key words:


congenital heart disease, adults, cardiac surgery, mortality, risk factors, robotic surgery.

Introduction:

The population of adults with congenital heart disease (CHD) is increasing with more than 85 % of children with CHD reaching adult age. The 32nd Bethesda Conference report estimated that there were approximately 2800 adults with CHD per one million population (1). More than half of them have moderate or high complexity defect and require specialized care, including surgery. Some adult patients with CHD, especially those operated in the 1960´s and 70´s have residual defects, most homografts have degenerated within 15 – 20 years, mild congenital lesions may have progressed and even acquired valve disease may appear. In some adults their CHD has gone unrecognized until late in their life (2). All these patients should be examined and operated in a specialized center. The presence of a surgeon with expertise in CHD is necessary, especially for complex CHD (3, 4, 5). However, our idea was, that ACHD patients should profit also from the presence of adult cardiac surgeon with expertise in valve-sparing surgery and an anesthesiologist with experience in high risk adults with ventricular dysfunction. We present our six-year experience and results of cardiac surgery in ACHD in the department of adult cardiac surgery with the presence of pediatric cardiac surgeon in the team.

The risk factors of surgery in ACHD are underestimated by Euroscore (6). Also the RACHS (Risk Adjustment for Congenital Heart Surgery) and ABC (Aristotle Basic Complexity Score) scores were primarily proposed for children with CHD and are not sufficient for ACHD (7, 8, 9). In our series we tried to find out the most important risk factors of mortality after the operation of ACHD.

Patients and methods:

In our tertiary referral Center for adults with congenital heart disease we look after 2530 adults with congenital heart disease (ACHD). In the period between 2005 and 2010 we operated in total on 459 ACHD, on average 77 operations of ACHD a year. The mean age of our ACHD patients was 40,4±15 years, there were 237 women (51,6 %). Operations of ACHD represent 9,5 % of all 4854 cardiac operations performed in our center in this period (tab 1).

Our cardiac surgery department performs about 800 operations a year, with increasing number of valve and complex surgery. In 2005 the valve surgery represented 54 %, in 2010 it increased to 68 % of all operations. The operations of ACHD are performed in the co-operation with the pediatric surgeon in the Adult Cardiac Surgery department.

All patients were examined by an experienced cardiologist, including an echocardiographic examination. Before all reoperations a CT angiogram was performed. The shunt was quantified by echocardiography, catheterisation, first-pass radionuclide cardiography or magnetic resonance. If pulmonary hypertension (PH) was suspected, catheterisation was performed. Coronary angiogram was performed in all patients over 40 years or if the coronary anomalies were suspected. If dysfunction of the right ventricle was suspected from echocardiography, the ejection fraction of the right ventricle was assessed by magnetic resonance. The ejection fraction of left or right ventricle ≤ 35 % was considered for severe dysfunction. Pulmonary hypertension (PH) was defined as the mean pulmonary artery pressure more than 25 mmHg.

The follow-up of operated patients is 100% with clinical and echocardiographic examinations 1 month, 1 year, 3 years and 5 years after the operation. If the patient does not come to the planned visit a telephone call to his family and/or general practitioner is performed.

In the evaluation of the risk factors of mortality we did not differentiate between early and late mortality because of the low numbers of deaths in both groups.

Statistical analysis was performed by chi-quadrate test with Yates correction and assessment of the odds ratio (OR) with 95 % confidence interval (CI). Significant differences were considered for p< 0.05.

Results

Diagnosis of operated ACHD patients

The rate of different diagnosis among operated on patients with congenital heart disease (CHD) and their mean age are summarized in table 2 and graph 1. The most frequent diagnosis was congenital aortic valve disease (30 %) including dilatation of the aorta, atrial septal defect type secundum (ASD) represented 22 % and tetralogy of Fallot (TOF) 13.5 % of operated ACHD. We operated on 25 patients with Ebstein anomaly (5.4 % ) and 27 complex CHD (5.9 %) including pulmonary atresia, unoperated d-transposition of the great arteries and primo-operations or reoperations in patients with Fontan circulation, table 2, graph 1.

Mini-invasive and robotic surgery in ACHD

Nineteen patients with atrial septa defect (ASD) including sinus venosus defect were operated on by robotic thoracoscopic surgery and 22 patients with ASD or mitral valve disease were operated by minithoracotomy. Altogether 41 patients (9 %) were operated by mini-invasive approach without sternotomy (picture 1, 2). None of these patients died in short or long-term follow up.

Mortality

The 30-days mortality was 1.1 %, five patients died early after the operation. Their diagnosis are summarized in table 3. The hospital mortality was 1.52 %. The long-term mortality was 1.3 %, another 6 patients died from cardiovascular reasons during a six-year follow-up.

Risk factors

Altogether 179 patients (39 %) had previously one or more heart operations, repeated reoperations were performed in 41 patients (9 %). The highest number of previous operations was found in pulmonary atresia, tetralogy of Fallot and other complex CHD with the maximum of 4 previous heart operations in a single patient.

Pulmonary hypertension was present in 52 operated patients (11.2 %), functional class NYHA III-IV was present in 30 % of patients and operation of 3 - 4 valves during single procedure was performed in 12 patients (2.6 %).

Significant risk factors for global mortality (short and long-term) were functional class NYHA III-IV before operation (p < 0.001; OR > 100), cyanosis (p < 0.001; OR 21.59) and severe systolic dysfunction of the left ventricle (p = 0.006; OR 13.33) or right ventricle (p < 0.001; OR 12.65) with the ejection fraction ≤ 35 %. We did not confirm increased risk for women gender (p = 0.203; OR 2.13), reoperations (p = 0.258; OR 1.88), age over 40 years (p = 0.619; OR 1.32) or pulmonary hypertension (p = 0.072; OR 3.68), table 4.

Discussion

At the present time there are living more adults than children with CHD (10, 11). While the surgery of children with CHD is usually well established and centralized, as in the Pediatric Cardiocentrum in Prague, there are different opinions concerning cardiac surgery in ACHD (10, 12, 13). Karamlou showed that the operation of ACHD by a pediatric heart surgeon decreases in-hospital rate of death, which was 1.87 % if the adult patients were operated by pediatric cardiac surgeon and 4.84 % if operated by non pediatric heart surgeon (11).

Our center started ACHD operations in 2005. Many adults with CHD have valve dysfunction, decreased ventricular performance and arrhythmias. Therefore we anticipated that a co-operation among pediatric heart surgeon, adult heart surgeons experienced in valve repair, anti-arrhythmic surgery and reoperations and the anesthesiologic team used to treat critically ill old patients with ventricular dysfunction would be a good combination for ACDH patients. Our results with very low hospital mortality, even in complex CHD confirm our strategy. The 30-days mortality of 1.1 % and in-hospital mortality of 1.52 % are comparable with the results of other experienced ACDH centers, in which the hospital mortality reaches 1.87 % to 2 % (12, 11, and 14) and 30-days mortality 1.5 % (15).

Our results confirm that ACHD patients may be safely treated in an experienced and specialized department of adult cardiac surgery in general hospital with a pediatric surgeon in the team. However, our results are in contradiction with Karamlou´s finding of the highest mortality (9.93 %) for the combination of a congenital heart surgeon operating in a general hospital (13). The difference can be explained by the quality of adult cardiac surgery in the general hospital. Prerequisite of the operations of ACHD in the department of adult cardiac surgery is high level of care, low mortality and extensive experience with high-risk patients. The hospital mortality of all operated patients in our department in the year 2010 was 1.2 %, which is lower than average.

The most significant risk factors of early and late death after operation were in our series: preoperative cyanosis, NYHA class III-IV and severe dysfunction of the left or right ventricle. Our results are in agreement with multicenter European study, which proved the same risk factors plus preoperative arrhythmias as the only risk factors for in-hospital mortality (11). Arrhythmias, ventricular dysfunction and cyanosis were the risk factors for long-term mortality in other centers (15). Unlike Karamlou, we did not confirm increased risk for VSD repair (12). We also did not confirm increased risk in patients with PH and older age, which was found in Putman´s single center analysis (15).

Our results suggest that in patients with severe residual findings after operation in childhood the reoperation should not be postponed until severe symptoms and ventricular dysfunction occur.

Conclusion

Operations of adults with CHD can be safely performed in experienced high volume adult cardiac surgery center. The excellent results with 30-days mortality 1.1 % and hospital mortality 1.52 % were achieved by the co-operation of adult cardiac surgeon experienced in valve surgery and pediatric surgeon. Robotic or mini-invasive surgery was eligible for 9 % of ACHD operations with zero mortality. The significant risk factors of death were NYHA class III-IV before operation, cyanosis and severe dysfunction of left or right ventricle. We did not confirm increased risk in women gender, in age over 40 years, in pulmonary hypertension, in reoperations nor in multi-valve surgery. It is reasonable to operate or reoperate ACHD with severe residual defects early, with less symptoms (NYHA I-II) and good systolic function of the left and right ventricle. Centralization of ACHD operations is necessary.

Abbreviations

• ACDH: adult congenital heart disease
• ASD: atrial septal defect
• AV: atrio-ventricular
• AVSD: atrio-ventricular septal defect
• CCTGA: congenitally corrected transposition of the great arteries
• CHD: congenital heart disease
• COA: coarctation of the aorta
• EF: ejection fraction
• LV: left ventricle
• MR: mitral regurgitation
• NYHA: New York Heart Association functional class
• PA: pulmonary atresia
• PH: pulmonary hypertension
• PS: pulmonary stenosis
• RV: right ventricle
• TOF: tetralogy of Fallot
• TR: tricuspid regurgitation
• VSD: ventricular septal defect

Acknowledgements

This project was supported by the grant of Czech Ministry of Health VZ MZOFNM2005 (VZMZO 64203-6306).

Statistical evaluation was performed by RNDr. Věra Lanská, CSc., Department of medical statistics, IKEM, Prague.

Adresa pro korespondenci:
Doc. MUDr. Jana Popelová, CSc.
Department of Cardiac Surgery, Hospital Na Homolce,
Roentgenova 2, 15030 Prague 5, Czech Republic.
e-mail: jana.popelova@homolka.cz,
tel. 605 513 540