Kong C W, Cheng Y K Y, To W W K, Leung T Y
Department of Obstetrics and Gynaecology, United Christian Hospital, Kwun Tong, Hong Kong.
Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Shatin, Hong Kong.
Hong Kong Med J. 2019 Feb;25(1):6-12. doi: 10.12809/hkmj187552. Epub 2019 Jan 18.
The aim of the present study was to calculate the prevalence of chromosomal abnormalities among antenatally diagnosed congenital heart diseases (CHDs), and the prevalence of 22q11.2 deletion in those with conotruncal CHDs versus isolated non-conotruncal CHDs.
All patients with antenatal ultrasound finding of fetal CHDs in two obstetric units in a 5-year period were retrospectively reviewed. Detected CHDs were classified as conotruncal if the malformation involved either the aortic outflow tract or the pulmonary outflow tract; otherwise they were classified as non-conotruncal. Karyotyping, fluorescence in situ hybridisation for 22q11.2 deletion (22q11FISH), and array comparative genomic hybridisation (aCGH) results were retrieved from patient medical records. The primary outcome was prevalence of chromosomal abnormalities in CHDs. The secondary outcomes were prevalence of 22q11.2 deletion and its prevalence in conotruncal versus non-conotruncal CHDs.
A total of 254 Chinese patients were diagnosed to have fetal CHDs. In all, 50 (19.7%) were found to have chromosomal abnormalities with seven (2.8%) patients having 22q11.2 deletion, of whom all seven had conotruncal CHDs and none had non-conotruncal CHDs (P<0.05). Conventional karyotyping detected 35 (70%) cases of the chromosomal abnormalities. The 22q11FISH detected three cases of 22q11.2 deletion; aCGH was performed to detect four cases of 22q11.2 deletion and eight other cases of copy number variations.
Our results suggest that invasive testing for karyotyping is recommended for fetal CHDs. Although the prevalence of 22q11.2 deletion was low, testing for 22q11.2 deletion should be offered for conotruncal CHDs.
本研究的目的是计算产前诊断的先天性心脏病（CHD）中染色体异常的患病率，以及圆锥动脉干型CHD与孤立性非圆锥动脉干型CHD患者中22q11.2缺失的患病率。
回顾性分析5年内两个产科单位产前超声检查发现胎儿患有CHD的所有患者。如果畸形累及主动脉流出道或肺动脉流出道，则检测到的CHD被分类为圆锥动脉干型；否则分类为非圆锥动脉干型。从患者病历中获取核型分析、22q11.2缺失的荧光原位杂交（22q11FISH）和阵列比较基因组杂交（aCGH）结果。主要结局是CHD中染色体异常的患病率。次要结局是22q11.2缺失的患病率及其在圆锥动脉干型与非圆锥动脉干型CHD中的患病率。
共有254例中国患者被诊断为胎儿患有CHD。其中，50例（19.7%）被发现存在染色体异常，7例（2.8%）患者存在22q11.2缺失，这7例均为圆锥动脉干型CHD，无1例为非圆锥动脉干型CHD（P<0.05）。传统核型分析检测到35例（70%）染色体异常病例。22q11FISH检测到3例22q11.2缺失；进行aCGH检测到4例22q11.2缺失和另外8例拷贝数变异。
我们的结果表明，对于胎儿CHD，建议进行侵入性核型分析检测。虽然22q11.2缺失的患病率较低，但对于圆锥动脉干型CHD应进行22q11.2缺失检测。
