2歳の次女にCAAs (サイズ不明) が認められており、治療反応性を祈るのみです。
Cardiovascular complications are the major cause of mortality and morbidity in patients with Kawasaki disease (KD).
The major complication of KD is coronary artery aneurysms (CAAs). Patients also can develop decreased myocardial contractility in the acute phase, valvular regurgitation, pericardial effusion, and peripheral artery aneurysms. Myocardial infarction and ischemia, the two most serious sequelae, only develop in patients with coronary disease.
The highest risk of morbidity and mortality is associated with giant CAAs (internal diameter >8 mm or z score ≥10). Up to one-third of such aneurysms become obstructed, and are associated with myocardial infarction, arrhythmias, or sudden death. Risk factors associated with CAAs include late diagnosis and late treatment with intravenous immunoglobulin (IVIG), age <1 year and >9 years, male gender, prolonged fever, failure to respond to initial IVIG therapy, and laboratory findings suggestive of persistent and severe inflammation.
Typically, aneurysms increase over the first four to six weeks after illness onset, and approximately 50 percent will regress to normal lumen diameter over the next two years. The likelihood that an aneurysm will regress to normal lumen diameter is most strongly related to its maximum diameter; giant aneurysms are least likely to regress.
Patients who have regressed or persistent aneurysms are assumed to be an "at-risk" population for early atherosclerotic disease; however, it remains unknown whether patients without coronary involvement are at increased risk for atherosclerosis.
In all patients with KD, cardiac testing includes echocardiography (eg, detection of CAAs and other cardiac abnormalities) and electrocardiography. When echocardiography is inadequate to image the coronary arteries, computed tomographic angiography (CTA) or magnetic resonance angiography (MRA) is used to fully delineate the coronary arterial tree.
Patients with coronary aneurysms should undergo stress testing with myocardial perfusion imaging to detect inducible ischemia on an annual basis. For patients with a history of giant coronary aneurysms, advanced imaging by cardiac catheterization, CTA, or MRA is performed one year after disease onset and then serially at an interval dependent upon clinical status and results of stress testing. If a cardiac catheterization is performed at one year, subsequent advanced imaging modalities should be noninvasive (eg, CTA or MRA) unless a catheter intervention is needed or noninvasive coronary imaging provides inadequate data to guide management. For asymptomatic patients with giant aneurysms and negative stress tests, advanced imaging is generally performed every three to five years. Exposure to ionizing radiation should be minimized wherever possible, favoring MRA at institutions where coronary MRA is feasible.
The management of cardiovascular sequelae of KD includes prevention of coronary thrombosis, treatment of patients with myocardial infarction and coronary thrombosis, and in some severe rare cases, cardiac transplantation.
We recommend all patients with KD and persistent CAAs receive antithrombotic therapy to prevent coronary thrombosis (Grade 1B). We tailor our therapy based on the size of the CAAs. In our practice, all patients receive low-dose aspirin therapy. Other antiplatelet agents (eg, clopidogrel) may be added to the drug regimen of patients with moderate to large CAAs. Patients with giant CAAs should be treated with aspirin together with anticoagulation (ie, warfarin or low-molecular-weight heparin).
In patients who suffer a myocardial infarction, we recommend emergent therapy for reperfusion and revascularization (Grade 1A). The therapeutic intervention is dependent on the size of the patient. In patients large enough for use of adult-size catheters, we recommend immediate angiography and mechanical restoration of blood flow (Grade 1A). In smaller patients, systemic alteplase (recombinant tissue-type plasminogen [tPA]) at a rate of 0.5 mg/kg per hour intravenously for six hours is administered together with aspirin and heparin.
In patients with clinical signs of coronary ischemia including reversible ischemia with exertion, we suggest that coronary artery revascularization intervention be performed (Grade 2C).
In our practice, the long-term follow-up care of patients with KD is generally consistent with the published recommendations of the American Heart Association． These guidelines are based on the coronary artery status of the patient, and outline the frequency of follow-up visits and include imaging, the use of medications including anticoagulation, and exercise restriction. Counseling regarding risk factors for atherosclerosis and healthy heart diet is provided, and screening for dyslipidemia is performed in all children with KD.
In addition, exercise recommendations are given to patients and their families based on the coronary artery status of the patient.