癌症手术前心血管检查的技巧

迈阿密海滩(EGMN)——如果需要在癌症手术前对患者进行评估，你对何时需要进行非侵入性心血管检查的了解有多少？

德克萨斯大学M.D. Anderson癌症中心的Sunil K. Sahai医生在迈阿密大学主办的围手术期医学会议上指出，在开始任何抗癌治疗之前，首先都应当请患者描述其功能状态。还要进行术前缺血的评估，评估结果可能对外科医生在术后处方心脏毒性较低的药物有指导意义。如果患者在化疗之前报告有气促，应检测是否有隐性缺血。

 “你所掌握的围手术期医学知识对癌症患者也适用，但对于癌症患者而言，围手术期医学也有其独特之处。”。癌症的生理负担及其治疗使得术前评估非常具有挑战性，但为了保证患者得到合理治疗，术前评估是非常有价值的。并且，对于部分病例而言，基于风险评估结果，无论患者或外科医生都会觉得应不再继续手术。

Sahai医生描述了1例真实患者带来的挑战：男性，60岁，在计划行喉全切和颈部淋巴结清扫术之前1周接受术前评估。表现为吞咽困难和咽喉痛。活检显示为环后鳞状细胞癌。合并银屑病、良性前列腺增生。患者曾于15年前因鼻咽癌接受手术和放疗。本次体检除双侧颈动脉杂音外，未见显著异常。多普勒超声显示为放疗引起的颈动脉下狭窄，并伴有弥漫性双侧动脉粥样硬化，狭窄超过70%。与生理性颈动脉狭窄患者相比，头颈部癌症患者发生短暂性脑缺血发作或脑血管意外的风险加倍。Sahai医生指出这是一个有争议的领域，因为“根据已有资料，尚未就如何处理得出明确结论”。“我们推迟了手术日期，并与所有相关医务人员进行讨论，最终决定在患者的右侧颈内动脉放置支架，将癌症手术推迟1个月，同时给予患者氯吡格雷和阿司匹林治疗。后来患者在阿司匹林治疗下接受了手术，目前状况良好。”

另有1例70岁的女性患者因膀胱癌计划行膀胱切除术，手术将耗时6 h。“该患者报告在晚上散步时有疲劳、气促和力竭的感觉。化疗之前，她可以连续步行8个街区和上2层楼梯，目前她仅能步行4个街区，并且在上1层楼梯后就需要停下来休息。她未描述有典型的心绞痛症状。”该患者肥胖，患有糖尿病，正在因高脂血症接受他汀治疗。她的病史还包括5年前有1次心肌梗死，仅采用药物治疗。Sahai医生指出，癌症可以消耗患者的体力，但这一病例的确切病因尚不明确。她的气促症状是否与冠心病、心力衰竭、肺动脉高压或有心脏毒性的化疗相关？是否应对患者进行检测，如进行超声心动检查评估心功能，进行压力测试评估缺血情况，或两项检测都需要？“因为该患者已接受有心脏毒性的化疗，我们应该对她进行压力超声检查。此外，BNP(B型脑利钠肽)水平可能有助于检出心肌病。我还将在患者的心功能和心率达到良好状态后，在他汀治疗下将患者送入手术室。”

Sahai医生认为，一般情况下，无心血管症状的患者可直接进入手术室。但如患者有症状，尤其是症状是在癌症治疗开始后出现的，则应做进一步的检查。

Sahai医生披露无相关利益冲突。

爱思唯尔  版权所有

BY DAMIAN MCNAMARA
Elsevier Global Medical News
Breaking News

MIAMI BEACH (EGMN) – 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.