Kawasaki disease (KD) is an acute febrile disease with systemic inflammatory vascular disease as the main pathology, in which coronary artery lesion (CAL) is the main complication; CAL occurs in 20-25% of children with untreated KD. The epidemiological survey of KD in Shanghai from 1998 to 2002 found that the incidence rate ranged from 16.18/100,000 to 36.18/100,000, 24.3% of KD patients were combined with cardiovascular lesions, of which 68% were coronary artery dilatation and 10% were coronary artery aneurysm, and the death rate was 0.26%. Similarly, in the new round of KD epidemiological survey in Shanghai from 2003 to 2008, the incidence of KD was still slightly higher than before, and the incidence of CAL did not change significantly. CAL due to KD has now become the most common acquired heart disease in children in developed countries or regions, and is one of the risk factors for ischemic heart disease in adulthood.
With the increased understanding of the long-term nature and severity of KD combined with CAL, long-term follow-up studies of this disease are particularly important, and based on these aspects, standardized follow-up of KD is particularly important for clinicians. This protocol refers to the management criteria of Kawasaki disease developed by the Japanese Pediatric Society and the American College of Cardiology in 2004, and combines the recent progress of KD research in China to discuss a standardized follow-up protocol for KD that is consistent with Chinese conditions.
1.No coronary artery aneurysm
No coronary artery dilatation lesion is seen on echocardiography in the acute phase within 1 month of onset; only coronary artery wall echogenicity enhancement is not meaningful; echocardiography is done after 2 weeks of disappearance of acute phase symptoms if the acute phase symptoms are prolonged for more than 2 weeks. Treatment: After the acute symptoms disappeared, aspirin maintenance dose of 3-5mg/(Kg.d) was applied until 3 months.
Follow-up: Follow-up review once a year at 1 month, 2 months, 3 months, 6 months, 1 year and 5 years after the onset of the disease, including cardiac ultrasound, electrocardiogram, platelets and blood sedimentation if necessary.
Exercise restriction: Not necessary.
2. Transient coronary artery dilatation lesion
Those who have had coronary dilatation within 1 month of onset and have returned to normal at 1 month. Treatment: The same as those without coronary artery dilatation, aspirin maintenance dose is applied until 3 months.
Follow-up: Follow-up review at 1 month, 2 months, 3 months, 6 months, 1 year and once a year for 5 years after the onset of the disease, including cardiac ultrasound, electrocardiogram and platelets.
Exercise restriction: not necessary.
In conjunction with the 2004 American Heart Association (AHA) [4] opinion on the long-term follow-up of children with KD, it was noted that in addition to routine cardiac echocardiography and electrocardiography, in patients presenting with coronary artery lesions, the systolic and diastolic function of the local vessel wall can remain abnormal for a long time even after normalization of the coronary morphology. Therefore, the application of stress echocardiography becomes very important. Since children with KD are mostly young and cannot cooperate with exercise examinations, pharmacological stress echocardiography is recommended. Therefore, drug stress echocardiography is recommended for the last examination of the above 2 types.
3.Mild coronary artery dilatation
Limited dilatation of coronary arteries with an internal diameter of less than 4 mm within 1 month of onset; less than 1.5 times the peripheral coronary artery internal diameter in older children over 5 years of age. Treatment: Aspirin maintenance therapy is recommended until 3 months after normalization of the coronary lesion.
Follow-up: Echocardiography was performed at appropriate intervals during the acute phase, and conventional cardiac ultrasound with drug-loaded echocardiography and electrocardiogram was repeated once a year at 1 month, 2 months, 3 months, 6 months, 1 year, and 5 years after onset. Exercise stress ECG is recommended. If cardiac stress test suggests myocardial ischemia, selective coronary angiography may be performed within 1 year of onset if necessary.
Strong physical activity should be appropriately limited during the follow-up period, but generally within 8 weeks of disease onset.
4.Moderate size coronary artery aneurysm
Coronary artery aneurysms with an internal diameter of 4 to 8 mm appear within 1 month of onset; 1.5 to 4 times the internal diameter of the peripheral coronary artery in older children over 5 years of age. Treatment: Continuous antithrombotic therapy is recommended.
Follow-up: Echocardiography was performed at appropriate intervals during the acute phase, and conventional cardiac ultrasound with drug-loaded echocardiography and conventional and exercise load ECG were repeated at 1 month, 2 months, 3 months, 6 months, 1 year, and every 6 months for 5 years after onset. Myocardial perfusion isotope examination and selective coronary angiography were performed according to the condition. Aneurysmal dilatation and string-like aneurysms in the anterior descending branches emanating from the left coronary trunk should be observed with caution. Such patients need to continue to take aspirin and antiplatelet drugs if the coronary aneurysm does not subside; the time to prohibit restriction of strong physical activity is decided according to the exercise load ECG.
5.Large coronary artery aneurysm
The internal diameter of coronary aneurysm exceeds 8mm in 1 month of onset, and is greater than 4 times the internal diameter of the peripheral coronary artery in older children over 5 years of age. The indications for coronary artery surgery for KD are currently considered as follows: ① end-stage KD coronary artery aneurysm with coronary artery damage after regular medical treatment; ② significant clinical symptoms or ECG changes, coronary artery aneurysm and coronary artery stenosis or coronary artery aneurysm combined with thrombus (iii) asymptomatic giant coronary aneurysm with potential rupture risk; (iv) coronary aneurysm with severe multiple coronary lesions or combined with other cardiac malformations requiring simultaneous treatment. Percutaneous coronary balloon angioplasty (PTCA) was started around 1990, and percutaneous intracoronary stent implantation and ablation are used for coronary lesions that cannot be treated by PTCA. The current indications for PTCA in KD in Japan include: (1) clinical manifestations of myocardial ischemia; (2) clinical manifestations of myocardial ischemia after exercise; and (3) no clinical manifestations of myocardial ischemia, but the stenosis of the anterior descending branch of the left coronary artery exceeds 75%.
Follow-up: It is necessary to apply echocardiography to observe the presence of intratumoral thrombus and electrocardiography to determine myocardial ischemia during the acute and risk periods. Selective coronary angiography may be performed at six months to one year follow-up based on clinical symptoms, ECG, echocardiography, and myocardial perfusion isotope examination suggesting ischemia. In the absence of coronary infarction, long-term anticoagulation therapy with aspirin and warfarin is followed up once a month during drug therapy after discharge, which can be changed to once every 3 months after the condition is stabilized. Such patients also need to review chest X-ray and exercise stress ECG once a year, limit daily activities and prohibit any sports.
6.Patients with coronary stenotic lesions and myocardial ischemic lesions
The treatment and follow-up can be extended until after the disease is stabilized. To prevent myocardial ischemia and heart failure, calcium antagonists, beta-blockers and ACEI can be used.
7.Other
Vascular lesions other than coronary arteries: If coronary artery lesions are present, the degree of these lesions will be used as a benchmark for appropriate treatment, follow-up and exercise restriction.
It is important to note that the follow-up of KD patients with coronary artery aneurysm and coronary stenosis needs to be individualized, as KD is an important cause of acquired cardiovascular disease in children and has an impact on the long-term quality of survival. Therefore, pediatricians should pay high attention not only to its early diagnosis and early intervention, but also to the prevention and treatment of long-term complications.