A 47-year-old woman presented with crescendo chest pain, palpitations, and shortness of breath on exertion for two days. She was hypotensive, tachycardic and tachypneic at the emergency department. Physical examination showed bilateral fine basal crepitation, a grade 2 decrescendo diastolic murmur, and bilateral pitting lower limb edema.
She was an active smoker and worked as warehouse logistic worker. She had no history of substance or alcohol misuse. There was no family history of cardiovascular disease or sudden death.
Chest X-ray showed congested basal lung fields with mild bilateral pleural effusion. Electrocardiography showed ST-segment depression in inferior leads. The clinical findings were suggestive of acute pulmonary oedema.
Transthoracic echocardiography (TTE) showed hypokinesia in the anterior wall as well as moderate-to-severe aortic insufficiency. An astute attending cardiologist noted immobile echogenic shadows in the ascending aorta on echocardiography obscuring the aortic valve, and thus arranged a computed tomography aortogram which excluded aortic dissection. Urgent cardiac catheterization showed an unusual picture of a slit-like left main coronary artery ostium, with the rest of the coronaries free from atherosclerotic plaque (Figure 1).
The atypical imaging findings prompted investigations for etiologies of infectious and inflammatory aortitis. Potential causative organisms of infectious aortitis included Treponema pallidum, Mycobacterium tuberculosis, Salmonella sp., Staphylococcus sp. and Campylobacter jejuni. Musculoskeletal examination and immunological assays were not suggestive of rheumatoid arthritis, systemic lupus erythematous, and Behcet disease. Ten days after hospitalization, the results of the Venereal Disease Research Laboratory (VDRL) test came back to be positive, which was further confirmed by a positive enzyme immunoassay for Treponema pallidum antibodies. Screening for co-infection of other sexually transmitted diseases including human immunodeficiency virus was negative.
While investigations for aortitis were ongoing, the case was discussed in a multidisciplinary team meeting. The decision was made to proceed with inpatient surgery for the critical left main stenosis and severe aortic regurgitation, after a brief period of medical optimization.
To facilitate operative planning, an electrocardiogram (ECG)-gated CT of the aortic root was performed, which demonstrated thickened and calcified circumferential plaque at the level of the sinotubular junction, causing subtotal obstruction of the left coronary ostium and partial obstruction of the right (Figure 2). Trans-esophageal echocardiography showed that the aortic valve was trileaflet. The leaflets were mildly calcified and thickened but free from vegetations. However, closure of the left coronary cusp was delayed, causing severe aortic insufficiency (Video 1).
The operation was performed two weeks after admission and commencement of guideline-directed heart failure and antimicrobial pharmacotherapy. Through a median sternotomy, aortic valve replacement, coronary ostioplasty and bypass grafting of the left anterior descending and obtuse marginal arteries was performed.
After institution of cardiopulmonary bypass and aortic cross-clamping, cold blood cardioplegia at 4 C was administered via an aortic root cannula. Although the heart initially achieved electrical quiescence, it recovered a slow junctional rhythm shortly after aortotomy. Ice slush was applied and cold fibrillatory arrest was achieved. After excision of valve leaflets and brief period of debridement lasting a few minutes, antegrade cardioplegia can be delivered smoothly to both coronary ostia (Video 2).
Coronary ostioplasty was then attempted. The right coronary ostium was exposed, revealing a normal calibre orifice surrounded by healthy intima. Although cardioplegia can be given via the left coronary ostium, the ostium appeared atretic and the surrounding intima was thickened and fibrotic. This necessitated bypass grafting to the left coronary circulation, sparing the right. The left internal mammary artery was anastomosed to the anterior descending; a great saphenous vein graft, harvested endoscopically, was anastomosed to an obtuse marginal branch.
A size 19 On-X mechanical aortic valve was used (CryoLife, Kennesaw, GA, USA). We elected not to perform a root enlargement or replacement because her body surface area was only 1.44 m2. Given the presence of aortitis and the poor tissue quality, a more aggressive operation may be hazardous.
The crossclamp time was 97 min and she came off bypass without inotropes. Her postoperative course was unremarkable. She completed an additional four-week course of oral doxycycline at a dose of 100 mg twice daily. Histopathological examination confirmed the diagnosis of syphilitic aortitis (Figures 3,4). Seroreversion was confirmed at 6 months.
TTE 6 months postoperatively showed a mean gradient of 8 mmHg. She expressed satisfaction with her treatment as her recovery was swift and she is now asymptomatic. An overview of the patient's course was presented in a timeline in Figure 5.