Age: 19 years
Working diagnosis: Kawasaki disease
The patient presented acutely with Kawasaki disease at the age of 20 months and was treated with aspirin. At age 23 months, she experienced chest pain with ST elevation seen in ECG leads II, III, and aVF, and had an inferior myocardial infarction. The infarction was followed by mild mitral regurgitation and impaired LV systolic function.
At 3 years of age, coronary angiography showed complete occlusion of the right coronary artery, with a giant aneurysm at the bifurcation of the left coronary artery. Repeat coronary angiography at age 10 showed in addition segmental stenosis of the left circumflex artery, though the patient was clinically stable. Segmental stenosis, which is a typical characteristic lesion as sequelae after Kawasaki disease, implies the development of several new small vessels representing recanalization after coronary artery occlusion.
By age 15, the patient had signs of heart failure due to ischemic cardiomyopathy. LV end-diastolic volume was increased. Multifocal premature ventricular contractions, as well as nonsustained ventricular tachycardia, were noted. Within a year she underwent coronary artery bypass grafting to the left anterior descending artery using the left internal mammary artery concomitantly with conventional reduction of the mitral valve annulus (by means of the so-called Kay-Reed method). The patient was said to be in NYHA class III in the early postoperative period. Warfarin was meticulously given for 1 year after surgery, in addition to aspirin.
One year after bypass surgery her functional class had improved to NYHA class II. A beta-blocker was added to her medications. She had no chest pain. Catheterization showed that the LV end-diastolic volume had decreased. The left internal mammary graft remained patent, but was extremely slender (“string sign”).
Comments: Kawasaki disease is an infantile acute febrile mucocutaneous lymph node syndrome. The inflammatory process can cause arteritis and, in a large proportion of patients, involves the coronary arteries in particular. This frequently leads to the formation of large aneurysms in the proximal coronaries, eventually with calcification of the wall of the aneurysm. Giant aneurysms (>8 mm) are likely to occlude with thrombosis, and this can lead to acute myocardial infarction. Acute myocardial infarction occasionally causes sudden death or impairs LV function, a major determinant of outcome in this population.
In this patient, mitral regurgitation worsened the LV dilatation and vice versa. Although surgical mitral valvuloplasty improved the regurgitation, LV dysfunction persisted.
In children undergoing coronary revascularization for Kawasaki disease, it is not rare for the bypass graft to become narrow and atretic. This likely reflects competition from native coronary flow. This phenomenon indicates the importance of a justifiable indication for coronary artery bypass grafting. It should be performed only when the native flow is severely impaired.
Aspirin 200 mg daily
Furosemide 40 mg daily
Spironolactone 50 mg twice daily
Metoprolol 25 mg twice daily
Comments: Today, anticoagulation with warfarin is routinely recommended for patients with Kawasaki disease, since giant aneurysms may become thrombosed, often within the first year after the acute phase of the disease. This was not known in the past, however, and this is the reason that this patient was not on warfarin at the time.
BP 104/60 mm Hg, HR 60 bpm, oxygen saturation 95%
Height 159 cm, weight 41 kg, BSA 1.35 m 2
Neck veins: Normal waveform, not elevated
Heart: The heart had a regular rhythm. The second heart sound was normally split. There was a grade 2/6 holosystolic murmur at the apex. Peripheral pulses were normal.
Abdomen: Liver was not palpable.
Extremities: Normal, no edema was present
Comments: The murmur is consistent with mitral regurgitation.
|Hemoglobin||13.5 g/dL (11.5–15.0)|
|Sodium||140 mmol/L (134–145)|
|Potassium||3.5 mmol/L (3.5–5.2)|
|Creatinine||0.6 mg/dL (0.6–1.2)|
|Blood urea nitrogen||2.8 mg/dL (2.5–6.5)|
OTHER RELEVANT LAB RESULTS
|Protein||6.5 g/dL (6.5–8.2)|
|Albumin||3.9 g/dL (3.6–5.5)|
|Total bilirubin||1.0 mg/dL (0.2–1.2)|
|AST||5 U/L (0–40)|
|ALT||7 U/L (0–35)|
|LDH||102 U/L (100–225)|
|CPK||34 U/L (30–200)|
|T-chol||130 mg/dL (130–220)|
|TG||38 mg/dL (30–130)|
|hANP||87 pg/mL (<40)|
|BNP||84.1 pg/mL (<20.0)|
Cardiothoracic ratio: 47%
Previous sternotomy. Normal cardiac size. There was a heavily calcified left coronary artery aneurysm, seen in cardiac silhouette.
Comments: The calcification seen is in the wall of the aneurysmal left coronary artery, indicative of a giant coronary aneurysm.
Another round and calcified lesion is vaguely seen around the third sternal wire from the top, which outlines the aneurysmal right coronary artery. This lesion is not as vivid as the one from the left coronary artery, probably because the right coronary one was more hidden between the sternum and vertebrae.
|Exercise protocol:||Modified Bruce|
|Reason for stopping:||Dyspnea|
|ECG changes:||Multifocal PVCs|
|Heart rate (bpm):||60||175|
|Percent of age-predicted max HR:||87|
|O 2 saturation (%):||95||97|
|Blood pressure (mm Hg):||104/60||122/74|
|Peak V o 2 (mL/kg/min):||15.3|
|Percent predicted (%):||31|
|Ve/V co 2 :||48|