Remetz M S, Quagliarello V
Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut.
Cardiol Clin. 1992 Feb;10(1):137-49.
Endovascular infections that involve the right side of the heart present their own unique etiologies, pathophysiologies, clinical manifestations, and therapeutic issues. The pathology of the vegetations of right-sided endocarditis is identical to that of left-sided endocarditis. These vegetations are irregular, friable masses of varying size the contain platelets, fibrin, RBCs, and microorganisms. These lesions serve as a nidus for deep-seated infection and produce sustained bacteremia. Right-sided endocarditis occurs in 5% to 10% of all cases of endocarditis. The most common predisposing factors are IV drug abuse and congenital heart disease. S. aureus is the most common pathogen. The clinical manifestations include fever, chills, rigor, dyspnea, pleuritic pain, productive cough, and hemoptysis. The cardiac manifestations can be notably absent early in the course of the disease, with only 20% of patients initially showing a significant murmur on physical examination. Peripheral embolic lesions can be seen. Echocardiography is helpful in identifying vegetations on the tricuspid valve in a significant proportion of patients. The chest radiograph is characteristic, showing features typical of multiple septic pulmonary emboli. The radiograph shows multiple, small, fuzzy, patchy, peripherally located densities that can change rapidly on serial films. Complications of right-sided endocarditis include pulmonary infarction, pulmonary abscess, progressive right-sided heart failure, and renal abnormalities. The treatment of right-sided endocarditis includes prolonged therapy, with high doses of IV bactericidal antibiotics. Four weeks of antibiotic therapy is generally required, but newer regimens using combination antibiotic therapy can be successful in sensitive strains of viridans group streptococci and S. aureus. Surgical resection of the tricuspid valve is recommended for organisms that do not respond to initial antibiotic therapy, fungal endocarditis, resistant relapsing organisms, or coexistent infection with S. aureus and P. aeruginosa. The prognosis of right-sided endocarditis is generally favorable when compared with left-sided endocarditis. The prognosis is especially favorable in IV drug abusers infected with S. aureus. Patients infected with fungal organisms, Pseudomonas or Serratia, have a worse prognosis. The presence of significant right-sided heart failure also imparts a worse prognosis.
累及心脏右侧的血管内感染有其独特的病因、病理生理、临床表现及治疗问题。右侧心内膜炎赘生物的病理与左侧心内膜炎相同。这些赘生物是大小不一、不规则、易碎的团块，包含血小板、纤维蛋白、红细胞及微生物。这些病变是深部感染的病灶，并导致持续性菌血症。右侧心内膜炎占所有心内膜炎病例的5%至10%。最常见的易感因素是静脉药物滥用和先天性心脏病。金黄色葡萄球菌是最常见的病原体。临床表现包括发热、寒战、 rigor（此词有误，可能是rigors，即剧烈寒战）、呼吸困难、胸膜炎性疼痛、咳痰及咯血。在疾病早期心脏表现可能不明显，仅20%的患者在体格检查时最初显示有明显杂音。可见外周栓塞性病变。超声心动图有助于在相当比例的患者中识别三尖瓣上的赘生物。胸部X线片具有特征性，显示多发性脓毒性肺栓塞的典型特征。X线片显示多个小的、模糊的、斑片状、位于周边的密度影，在连续的片子上可迅速变化。右侧心内膜炎的并发症包括肺梗死、肺脓肿、进行性右侧心力衰竭及肾脏异常。右侧心内膜炎的治疗包括长时间治疗，使用大剂量静脉注射杀菌性抗生素。一般需要四周的抗生素治疗，但使用联合抗生素治疗的新方案对草绿色链球菌和金黄色葡萄球菌的敏感菌株可能有效。对于对初始抗生素治疗无反应的病原体、真菌性心内膜炎、耐药复发性病原体或合并金黄色葡萄球菌和铜绿假单胞菌感染，建议手术切除三尖瓣。与左侧心内膜炎相比，右侧心内膜炎的预后通常较好。感染金黄色葡萄球菌的静脉药物滥用者预后尤其良好。感染真菌、假单胞菌或沙雷菌的患者预后较差。存在严重的右侧心力衰竭也提示预后较差。
