Methodology helps in decision making about surgery for congenital heart patients

A new methodology developed by researchers at the Universidade de São Paulo School of Medicine’s Heart Institute (InCor/USP) makes it possible to evaluate children and adolescents with congenital heart disease and to identify those with a higher risk of death or complications as a result of corrective surgery.

By Karina Toledo

Agência FAPESP – A new methodology developed by researchers at the Universidade de São Paulo School of Medicine’s Heart Institute (InCor/USP) makes it possible to evaluate children and adolescents with congenital heart disease and to identify those with a higher risk of death or complications as a result of corrective surgery. In addition to avoiding unnecessary suffering on the part of these young people and their families, the objective of the project is to optimize the institution’s resources byreducing costs and time on the waiting list for treatment.

Currently, there are some 560 patients with congenital heart problems waiting for treatment at InCor. “Wait time depends on the seriousness of the patient’s condition, but it can be more than two years”, says physiotherapist Emilia Nozawa, coordinator of the study.

Nozawa, Chief Physiotherapist at InCor and advisor for the FMUSP Cardiology Program, created a set of tests to measure, among other indicators, cardiac capacity when patients are submitted to physical exertion and pulmonary function tests. She then identified some variables that may have a positive or negative influence on the results of the surgical procedure. 

The study, funded by FAPESP under its Research Support-Regular program, involved the doctoral work of Angela Sachiko Inoue, for which Nozawa is an advisor, and which should be defended in mid-2012.
The study involved 81 patients aged 7-18 years, who were evaluated at three stages: before surgery, on the day they were released from the hospital, and 90 days after discharge from the hospital.

Overall, 50 of the 81 patients completed the three phases of the study. Five died and 4 stayed in the hospital for a longer period than the expected 30 days. The other 22 did not return for the third evaluation.

All the patients underwent a 6-minute walk test (TC6 M), which evaluated how many meters the patients were able to walk during the time limit. The patient’s oxygen saturation was measured before and after the physical exertion along with the level of exhaustion.

The patients were also subjected to spirometry assessment to evaluate pulmonary function, and an exam for measuring Peak Inspiratory Pressure (PIP) and Peak Expiratory Flow Rate (PEFR); in other words, the muscular exertion that the respiratory system expends to contract and relax was determined.

Variations in cardiac frequency and arterial pressure were also measured. The data were collected between January 2009 and June 2011.

“The patients who walked less than 422 meters in the pre-operative phase, exhibited little variation in heart rate, and had oxygen saturation lower than 95% were those who died or had extended stays in the ICU due to complications,” said Nozawa.

Mitigating measures

In Nozawa’s opinion, the best approach for high-risk cases is to take mitigating measures. “Extended hospital stays are very hard on family structures, overload the hospital and don’t allow for patient rotation. Plus, these children go through a great deal of suffering and finally, they end up dying,” she affirmed.

According to her, this represents a problem that is being encountered with increasing frequency. As medicine evolves, more newborns with congenital heart problems reach adolescence and adulthood.
Nozawa stresses that evaluating the seriousness of a group of alterations that are so diverse is difficult but necessary, and has serious therapeutic implications.

Among the 81 patients who participated in the study, 70% had undergone previous surgeries. The average price for congenital heart treatment through the Unified Health Care System, or SUS, is approximately R$ 12,000. This price does not include the costs for medical supplies, ICU treatment or nursing care.

The study coordinated by Nozawa also involved the collaboration of Ana Cristina Sayuri Tanaka and Antonio Augusto Lopes, from the InCor Congenital Heart Services Department. Filomena Regina Gomes Galas, director of the Anesthesiology and Surgical ICU at InCor, also collaborated on the study. 

Partial results were presented at the Congress of the São Paulo State Cardiology Society, at the International Symposium of Respiratory Physiotherapy held in Porto Alegre and at the European Respiratory Society Annual Congress in Barcelona. They were also submitted to Revista Portuguesa de Cardiologia.