Karalis D G, Bansal R C, Hauck A J, Ross J J, Applegate P M, Jutzy K R, Mintz G S, Chandrasekaran K
Department of Internal Medicine (Cardiology) Hahnemann University, Philadelphia, Pa.
Circulation. 1992 Aug;86(2):353-62. doi: 10.1161/01.cir.86.2.353.
Secondary involvement of the mitral-aortic intervalvular fibrosa and the anterior mitral leaflet (subaortic structures) can occur in patients with aortic valve endocarditis. The secondary involvement of these structures occurs as a result of direct extension of the infection from the aortic valve or as a result of an infected aortic regurgitant jet striking the ventricular surfaces of the mitral-aortic intervalvular fibrosa and the anterior mitral leaflet. The abscess of mitral-aortic intervalvular fibrosa can expand to form an aneurysm. Subsequently, this mitral-aortic intervalvular fibrosa aneurysm can develop a perforation and communicate with the left atrium, resulting in the systolic regurgitation of blood from the left ventricular outflow tract into the left atrium. Secondary infection can also occur on the ventricular surface of the anterior mitral leaflet and result in the formation of an aneurysm or perforation of anterior mitral leaflet.
This study examines the utility of transesophageal echocardiography in the detection of these subaortic complications in 55 consecutive patients with aortic valve endocarditis. A total of 24 patients (44%) had involvement of subaortic structures, including four with an abscess in the mitral-aortic intervalvular fibrosa, four with mitral-aortic intervalvular fibrosa aneurysm, seven with perforation of the mitral-aortic intervalvular fibrosa with communication into the left atrium, two with an aneurysm of the anterior mitral leaflet, and seven with perforation of the anterior mitral leaflet. The transesophageal echocardiographic findings were confirmed at surgery in 20 patients and at necropsy in two. By comparison, transthoracic echocardiography visualized these lesions in five of 24 patients (21%), including none of four with mitral-aortic intervalvular fibrosa abscesses, two of four with mitral-aortic intervalvular fibrosa aneurysms, one of seven with mitral-aortic intervalvular fibrosa perforations, one of two with anterior mitral leaflet aneurysms, and one of seven anterior mitral leaflet perforations. Eccentric mitral regurgitation-type systolic jets were noted in eight additional patients by transthoracic color flow imaging, and this finding suggested the possibility of these unusual subaortic complications. If these patients are included, then transthoracic echocardiography suggested the presence of these subaortic complications in 13 of 24 patients (54%).
The results indicate that 1) involvement of the subaortic structures in patients with aortic valve endocarditis may be more common than previously recognized, 2) patients with aortic valve endocarditis and eccentric jets of mitral regurgitation on transthoracic echocardiography should undergo further evaluation by transesophageal echocardiography to exclude these unusual complications, 3) precise recognition of these complications is of value in the optimal medical and surgical management of these patients, and 4) these complications may be responsible for unexplained congestive heart failure and hemodynamic deterioration in some patients with aortic valve endocarditis.
主动脉瓣心内膜炎患者可出现二尖瓣 - 主动脉瓣间纤维结缔组织及二尖瓣前叶（主动脉瓣下结构）的继发性受累。这些结构的继发性受累是由于感染从主动脉瓣直接蔓延，或因感染性主动脉反流束冲击二尖瓣 - 主动脉瓣间纤维结缔组织及二尖瓣前叶的心室面所致。二尖瓣 - 主动脉瓣间纤维结缔组织脓肿可扩大形成动脉瘤。随后，这种二尖瓣 - 主动脉瓣间纤维结缔组织动脉瘤可发生穿孔并与左心房相通，导致血液从左心室流出道在收缩期反流至左心房。二尖瓣前叶心室面也可发生继发性感染，导致二尖瓣前叶形成动脉瘤或穿孔。
本研究探讨经食管超声心动图在连续55例主动脉瓣心内膜炎患者中检测这些主动脉瓣下并发症的效用。共有24例患者（44%）出现主动脉瓣下结构受累，包括4例二尖瓣 - 主动脉瓣间纤维结缔组织脓肿、4例二尖瓣 - 主动脉瓣间纤维结缔组织动脉瘤、7例二尖瓣 - 主动脉瓣间纤维结缔组织穿孔并与左心房相通、2例二尖瓣前叶动脉瘤、7例二尖瓣前叶穿孔。20例患者的经食管超声心动图检查结果在手术中得到证实，2例在尸检中得到证实。相比之下，经胸超声心动图在24例患者中的5例（21%）显示了这些病变，其中4例二尖瓣 - 主动脉瓣间纤维结缔组织脓肿患者均未显示，4例二尖瓣 - 主动脉瓣间纤维结缔组织动脉瘤患者中有2例显示，7例二尖瓣 - 主动脉瓣间纤维结缔组织穿孔患者中有1例显示，2例二尖瓣前叶动脉瘤患者中有1例显示，7例二尖瓣前叶穿孔患者中有1例显示。经胸彩色血流成像在另外8例患者中发现偏心二尖瓣反流型收缩期血流束，这一发现提示可能存在这些不寻常的主动脉瓣下并发症。如果将这些患者包括在内，那么经胸超声心动图提示24例患者中有13例（54%）存在这些主动脉瓣下并发症。
结果表明，1）主动脉瓣心内膜炎患者主动脉瓣下结构受累可能比之前认识到的更为常见；2）经胸超声心动图显示二尖瓣反流偏心血流束的主动脉瓣心内膜炎患者应接受经食管超声心动图进一步评估，以排除这些不寻常的并发症；3）准确识别这些并发症对这些患者的最佳药物和手术治疗具有重要价值；4）这些并发症可能是部分主动脉瓣心内膜炎患者出现不明原因的充血性心力衰竭和血流动力学恶化的原因。
