Ⅳ期肺癌後の呼吸不全に洞機能不全を認めた1例

Sick Sinus Syndrome in a Patient with Respiratory Failure After Treatment of Stage Ⅳ Lung Cancer

要旨　患者は67歳，男性．10年前にⅣ期肺扁平上皮癌と診断され抗癌剤投与と放射線療法を受けた．7年前に癌性胸膜炎を発症し放射線療法を受けた．その後，右肺は無気肺となり，重度の呼吸不全状態となった．今回，意識消失発作を起こし洞機能不全症候群と診断された．その原因として，年齢によるものと放射線障害によるものが考えられた．ペースメーカ植込み後，意識消失はみられなくなり，呼吸不全も改善した．本症例における呼吸不全増悪の一因として，徐脈からの心不全の関与が考えられた．

　A 67-year-old man had been diagnosed with stage Ⅳ non-small cell lung cancer 10 years before, when he had undergone chemotherapy and radiation therapy. He had suffered carcinomatous pleuritis 7 years before, and had undergone radiation therapy again. Thereafter, he had suffered atelectasis of the right lung and occasional pneumonia of the left lung with CO₂ narcosis. He was re-admitted due to sick sinus syndrome. After pacemaker implantation, the patient reported the reduction of dyspnea by improvement of heart failure. This is a rare case who survived more 10 years after being diagnosed with stage 4 non-small cell lung cancer,and suggests the risk of heart failure due to bradycardia.