MIAMI BEACH – When you are called to assess a patient before cancer surgery, how do you know when noninvasive cardiovascular testing is warranted?
Start by asking patients to describe their functional status before they started any treatment to combat their cancer, Dr. Sunil K. Sahai said.
Also assess for any ischemia preoperatively, because its presence might direct a surgeon to prescribe a less cardiotoxic postoperative treatment for your patient, Dr. Sahai said at a meeting on perioperative medicine sponsored by the University of Miami. Occult ischemia might be found if a patient reports shortness of breath during prior chemotherapy administration, he added.
"Everything you’ve heard about perioperative medicine is true for cancer patients, but they are also unique," Dr. Sahai said. The physiologic burden of cancer and its treatment makes preoperative evaluation challenging, but it’s worth doing right to ensure the patient receives the optimal therapy. Also, in some cases, either the patient or surgeon will decide not to proceed with surgery based on your risk assessment, said Dr. Sahai, medical director of the Internal Medicine Perioperative Assessment Center at the University of Texas M.D. Anderson Cancer Center in Houston.
To illustrate some of the challenges, Dr. Sahai described an actual patient, a 60-year-old man referred for preoperative assessment 1 week before a scheduled neck dissection and total laryngectomy. He presented with dysphagia and sore throat. A biopsy revealed postcricoid squamous cell carcinoma. He was otherwise healthy, except for psoriasis and benign prostatic hyperplasia. He had undergone surgery and radiation for nasopharyngeal cancer 15 years earlier. The current physical examination was unremarkable, except for bilateral carotid bruits. Doppler ultrasound findings led to a diagnosis of radiation-induced carotid stenosis with diffuse, bilateral atherosclerosis and greater than 70% stenosis.
Head and neck cancer patients can have double the risk of transient ischemic attack or cerebrovascular accident, compared with a patient with normal pathologic narrowing of the carotid arteries, Dr. Sahai said. This is a controversial area because "data are not clear on what to do."
"We postponed and all discussed with all the providers involved," Dr. Sahai said. A stent was placed in the patient’s right internal carotid artery, and cancer surgery was delayed for 1 month while the patient took clopidogrel and aspirin. "He then went to the operating room on aspirin, and he did well."
Another case, a 70-year-old woman scheduled for a 6-hour cystectomy for bladder cancer, raised issues around preoperative cardiovascular assessment. "She reports fatigue and shortness of breath with exertion on her evening walks," Dr. Sahai said. "Before chemotherapy, she was able to walk eight blocks and up two flights of stairs without stopping. Now she can walk only four blocks and stops to rest between flights." She does not describe typical angina symptoms, he added.
The patient is obese, has diabetes mellitus, and is taking a statin for hyperlipidemia. She does not report any angina symptoms. Her history includes a myocardial infarction 5 years earlier addressed with medical management only.
Cancer can sap a patient’s energy, but the precise etiology in this case was unclear, Dr. Sahai said. Was her shortness of breath related to coronary artery disease, heart failure, pulmonary hypertension, or treatment with cardiotoxic chemotherapy? Should the patient be tested, for example, with an echocardiogram for heart function, stress test for ischemia, or both?
"Because this patient had received cardiotoxic chemotherapy ... we would do a stress echo on this patient," Dr. Sahai said. "In addition, BNP [B-type natriuretic peptide] levels may be helpful to detect cardiomyopathy. I would also optimize cardiac function and heart rate and send her to the operating room with the statin on board."
Patients with no cardiovascular symptoms can generally go to the operating room. If a patient is symptomatic, however, especially if the symptoms are new since cancer therapy was begun, Dr. Sahai said he generally considers further testing and work-up.
Dr. Sahai had no relevant financial disclosures.