High-risk factors of cardiac contractility reserve in the third trimester of high-risk pregnancy and the significance of phonocardiogram test in evaluation of pregnant women′s cardiac contractility reserve

doi:10.3877/cma.j.issn.1673-5250.2019.05.005

Objective

To investigate the high-risk factors that may affect the cardiac contractility reserve (CCR) of high-risk pregnant women in the third trimester, and to evaluate the value of the phonocardiogram test (PCGT) in assessment of CCR of pregnant women in the third trimester.

Methods

From May 1, 2013 to July 31, 2013, a total of 65 cases of high-risk pregnant women with CCR abnormalities in the third trimester (28-41^{+ 6} weeks of gestation) in Chengdu Women′s and Children′s Central Hospital were selected as research subjects and included in study group. Simultaneously, others 489 cases of normal CCR pregnant women in the third trimester (28-41^{+ 6} gestational weeks) during the same period and in the same hospital were selected as control and included in control group. PCGT were used to measure CCR-related indicators, including heart rate, ratio of the amplitude of the first heart sound to the second heart sound (S1/S2), ratio of diastolic to systolic duration (D/S), and ratio of S1 amplitude at tricuspid valve auscultation area to that at mitral auscultation area (T1/M1). Through questionnaires and medical history taking, 14 factors that might affect CCR-related indicators between two groups of pregnant women were collected, and multivariate unconditional logistic regression analysis was performed to analyze the high-risk factors that might affect the CCR of pregnant women in the third trimester. The consistency of CCR indexes S1/S2, D/S and echocardiographic detection of cardiac ejection fraction (EF) and electrocardiogram results in diagnosis of cardiac function in pregnant women in the third trimester were analyzed. This study was in line with the requirements of World Medical Association Declaration of Helsinki revised in 2013. All participants confirmed and signed consent forms for clinical trials.

Results

①Combined with high-risk pregnancies, combined with family history of cardiovascular and cerebrovascular diseases, ≥29-35 years old, ≥35 years old, systolic blood pressure ≥140-160 mmHg (1 mmHg=0.133 kPa) and systolic blood pressure ≥160 mmHg were independent risk factors for abnormal heart rate (OR=3.158, 1.816, 1.760, 1.901, 6.066, 17.055, 95%CI: 1.555-6.415, 1.156-2.853, 1.046-2.960, 1.132-3.194, 1.131-32.548, 2.353-123.599, P=0.001, 0.010, 0.033, 0.015, 0.035, 0.005). Junior college and above education levels of pregnant women was an independent protective factor for heart rate (OR=0.529, 95%CI: 0.321-0.870, P=0.012). ②With 32-34^{+ 6} gestational weeks, combined with high-risk pregnancy, and systolic blood pressure ≥140-160 mmHg, systolic blood pressure≥160 mmHg were independent risk factors for abnormal S1/S2 (OR=2.400, 5.842, 4.293, 12.875, 95%CI: 1.265-4.553, 2.966-11.506, 1.460-26.467, 2.496-113.852, P=0.007, 0.028, 0.035, 0.005). ③Combined with high-risk pregnancy, diastolic blood pressure ≥90-110 mmHg and diastolic blood pressure ≥110 mmHg were independent risk factors for abnormal D/S (OR=4.706, 1.993, 6.458, 95%CI: 2.556-8.665, 1.532-17.708, 2.391-28.166, P=0.020, 0.010, 0.047). ④Gravidity≥4 times was an independent risk factor for abnormal T1/M1 (OR=9.555, 95%CI: 1.147-77.955, P=0.037). ⑤Among 65 cases of abnormal CCR pregnant women in the third trimester(study group), the coincidence rates of S1/S2 with cardiac EF and routine electrocardiogram results in diagnosis of cardiac function in pregnant women in the third trimester were 93.8% (61/65) and 89.2% (58/65), respectively. And the coincidence rates of D/S with these two examination results were the same as S1/S2.

Conclusions

Multiple pregnancies, 32-34^{+ 6} gestational weeks, combined with high-risk pregnancies, combined with family history of cardiovascular and cerebrovascular diseases, ≥29 years old, systolic blood pressure ≥140 mmHg, and diastolic blood pressure ≥90 mmHg are risk factors for abnormal CCR in pregnant women in the third trimester. We should strengthen the prenatal care for these pregnant women. The consistency rates of CCR indexes with echocardiography(EF) and routine electrocardiogram results are high, and PCGT has the advantages of easy to operation and low cost in assessment of CCR in pregnant women in the third trimester, and can be used to screen the CCR of these pregnant women.

Key words: Myocardial contraction, Cardiac contractility reserve, Phonocardiogram test, Heart rate, S1/S2, D/S, T1/M1, Pregnancy trimester, third, Pregnant women

表1 晚孕期孕妇CCR异常可能影响因素的多因素非条件logistic回归分析的变量含义及其赋值

自变量/因变量	变量名	赋值
心率	y₁	y₁＝0表示心率<100次/min，y₁＝1表示心率≥100次/min
S1/S2	y₂	y₂＝0表示S1/S2<3.8，y₂＝1表示S1/S2≥3.8
D/S	y₃	y₃＝0表示D/S<1，y₃＝1表示D/S≥1
T1/M1	y₄	y₄＝0表示T1/M1<3，y₄＝1表示T1/M1≥3
年龄	x₁	x₁＝0表示年龄<25岁，x₁＝1表示年龄≥25～29岁，x₁＝2表示年龄≥29～35岁，x₁＝3表示年龄≥35岁
职业	x₂	x₂＝0表示未就业，x₂＝1表示从事体力劳动，x₂＝2表示从事脑力劳动，x₂＝3表示从事体力和脑力劳动
文化程度	x₃	x₃＝0表示文化程度为高中及以下，x₃＝1表示大专及以上
居住地	x₄	x₄＝0表示居住地为农村，x₄＝1表示居住地为城市
孕次	x₅	x₅＝0表示孕次为1次，x₅＝1表示孕次为2次，x₅＝2表示孕次为3次，x₅＝3表示孕次为≥4次
产次	x₆	x₆＝0表示产次为0，x₆＝1表示产次为1次，x₆＝2表示产次为2次，x₆＝3表示产次≥3次
孕龄	x₇	x₇＝0表示孕龄为28～31^＋6孕周，x₇＝1表示孕龄为32～34^＋6孕周，x₇＝2表示孕龄为35～41^＋6孕周
是否合并高危妊娠	x₈	x₈＝0表示未合并高危妊娠，x₈＝1表示合并高危妊娠
异常孕产史	x₉	x₉＝0表示无异常孕产史，x₉＝1表示有异常孕产史
心、脑血管疾病家族史	x₁₀	x₁₀＝0表示未合并心、脑血管疾病家族史，x₁₀＝1表示合并心、脑血管疾病家族史
孕前BMI	x₁₁	x₁₁＝0表示孕前BMI≥18.5～25.0 kg/m²，x₁₁＝1表示孕前BMI≥25.0～30.0 kg/m²，x₁₁＝2表示孕前BMI≥30 kg/m²
孕期体重增加值	x₁₂	x₁₂＝0表示孕期体重增加值为≤11.5 kg，x₁₂＝1表示孕期体重增加值为≥11.5～16.0 kg，x₁₂＝2表示孕期体重增加值为≥16.0 kg
收缩压	x₁₃	x₁₃＝0表示收缩压<130 mmHg，x₁₃＝1表示收缩压≥130～140 mmHg，x₁₃＝2表示收缩压≥140～160 mmHg，x₁₃＝3表示收缩压≥160 mmHg
舒张压	x₁₄	x₁₄＝0表示舒张压<90 mmHg，x₁₄＝1表示收缩压≥90～110 mmHg，x₁₄＝2表示收缩压≥110 mmHg

表1 晚孕期孕妇CCR异常可能影响因素的多因素非条件logistic回归分析的变量含义及其赋值

自变量/因变量	变量名	赋值
心率	y₁	y₁＝0表示心率<100次/min，y₁＝1表示心率≥100次/min
S1/S2	y₂	y₂＝0表示S1/S2<3.8，y₂＝1表示S1/S2≥3.8
D/S	y₃	y₃＝0表示D/S<1，y₃＝1表示D/S≥1
T1/M1	y₄	y₄＝0表示T1/M1<3，y₄＝1表示T1/M1≥3
年龄	x₁	x₁＝0表示年龄<25岁，x₁＝1表示年龄≥25～29岁，x₁＝2表示年龄≥29～35岁，x₁＝3表示年龄≥35岁
职业	x₂	x₂＝0表示未就业，x₂＝1表示从事体力劳动，x₂＝2表示从事脑力劳动，x₂＝3表示从事体力和脑力劳动
文化程度	x₃	x₃＝0表示文化程度为高中及以下，x₃＝1表示大专及以上
居住地	x₄	x₄＝0表示居住地为农村，x₄＝1表示居住地为城市
孕次	x₅	x₅＝0表示孕次为1次，x₅＝1表示孕次为2次，x₅＝2表示孕次为3次，x₅＝3表示孕次为≥4次
产次	x₆	x₆＝0表示产次为0，x₆＝1表示产次为1次，x₆＝2表示产次为2次，x₆＝3表示产次≥3次
孕龄	x₇	x₇＝0表示孕龄为28～31^＋6孕周，x₇＝1表示孕龄为32～34^＋6孕周，x₇＝2表示孕龄为35～41^＋6孕周
是否合并高危妊娠	x₈	x₈＝0表示未合并高危妊娠，x₈＝1表示合并高危妊娠
异常孕产史	x₉	x₉＝0表示无异常孕产史，x₉＝1表示有异常孕产史
心、脑血管疾病家族史	x₁₀	x₁₀＝0表示未合并心、脑血管疾病家族史，x₁₀＝1表示合并心、脑血管疾病家族史
孕前BMI	x₁₁	x₁₁＝0表示孕前BMI≥18.5～25.0 kg/m²，x₁₁＝1表示孕前BMI≥25.0～30.0 kg/m²，x₁₁＝2表示孕前BMI≥30 kg/m²
孕期体重增加值	x₁₂	x₁₂＝0表示孕期体重增加值为≤11.5 kg，x₁₂＝1表示孕期体重增加值为≥11.5～16.0 kg，x₁₂＝2表示孕期体重增加值为≥16.0 kg
收缩压	x₁₃	x₁₃＝0表示收缩压<130 mmHg，x₁₃＝1表示收缩压≥130～140 mmHg，x₁₃＝2表示收缩压≥140～160 mmHg，x₁₃＝3表示收缩压≥160 mmHg
舒张压	x₁₄	x₁₄＝0表示舒张压<90 mmHg，x₁₄＝1表示收缩压≥90～110 mmHg，x₁₄＝2表示收缩压≥110 mmHg

表2 晚孕期孕妇心力储备指标心率异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
年龄(岁)		?	?	?	?	?	?
?	≥25～29	－0.365	0.142	6.605	0.459	0.694	0.264～1.825
?	≥29～35	0.565	0.365	2.396	0.033	1.760	1.046～2.960
?	≥35	0.642	－0.489	1.724	0.015	1.901	1.132～3.194
大专及以上		－0.638	－0.354	3.247	0.012	0.529	0.321～0.870
合并高危妊娠		1.150	0.852	1.823	0.001	3.158	1.555～6.415
合并心、脑血管疾病家族史		0.597	0.253	1.488	0.010	1.816	1.156～2.853
收缩压(mmHg)		?	?	?	?	?	?
?	≥130～140	1.593	0.803	3.936	0.056	4.920	0.958～25.260
?	≥140～160	1.803	1.109	2.644	0.035	6.066	1.131～32.548
?	≥160	2.836	1.182	6.300	0.005	17.055	2.353～123.599

表2 晚孕期孕妇心力储备指标心率异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
年龄(岁)		?	?	?	?	?	?
?	≥25～29	－0.365	0.142	6.605	0.459	0.694	0.264～1.825
?	≥29～35	0.565	0.365	2.396	0.033	1.760	1.046～2.960
?	≥35	0.642	－0.489	1.724	0.015	1.901	1.132～3.194
大专及以上		－0.638	－0.354	3.247	0.012	0.529	0.321～0.870
合并高危妊娠		1.150	0.852	1.823	0.001	3.158	1.555～6.415
合并心、脑血管疾病家族史		0.597	0.253	1.488	0.010	1.816	1.156～2.853
收缩压(mmHg)		?	?	?	?	?	?
?	≥130～140	1.593	0.803	3.936	0.056	4.920	0.958～25.260
?	≥140～160	1.803	1.109	2.644	0.035	6.066	1.131～32.548
?	≥160	2.836	1.182	6.300	0.005	17.055	2.353～123.599

表3 晚孕期孕妇心力储备指标S1/S2异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
大专及以上		－0.877	0.473	3.437	<0.001	0.546	0.103～0.524
孕龄(周)		?	?	?	?	?	?
?	32～34^＋6	0.875	0.618	2.005	0.007	2.400	1.265～4.553
?	35～41^＋6	0.768	0.875	0.771	0.070	2.156	0.950～3.627
合并高危妊娠		1.765	0.869	4.125	0.028	5.842	2.966～11.506
收缩压(mmHg)		?	?	?	?	?	?
?	≥130～140	1.272	0.963	1.745	0.056	3.568	0.847～21.373
?	≥140～160	1.457	0.873	7.762	0.035	4.293	1.460～26.467
?	≥160	2.555	1.136	5.058	0.005	12.875	2.496～113.852

表3 晚孕期孕妇心力储备指标S1/S2异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
大专及以上		－0.877	0.473	3.437	<0.001	0.546	0.103～0.524
孕龄(周)		?	?	?	?	?	?
?	32～34^＋6	0.875	0.618	2.005	0.007	2.400	1.265～4.553
?	35～41^＋6	0.768	0.875	0.771	0.070	2.156	0.950～3.627
合并高危妊娠		1.765	0.869	4.125	0.028	5.842	2.966～11.506
收缩压(mmHg)		?	?	?	?	?	?
?	≥130～140	1.272	0.963	1.745	0.056	3.568	0.847～21.373
?	≥140～160	1.457	0.873	7.762	0.035	4.293	1.460～26.467
?	≥160	2.555	1.136	5.058	0.005	12.875	2.496～113.852

表4 晚孕期孕妇心力储备指标D/S异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
年龄(岁)		?	?	?	?	?	?
?	≥25～29	0.149	0.350	0.180	0.063	1.160	0.584～2.306
?	≥29～35	－0.018	0.351	0.003	0.050	0.982	0.493～1.957
?	≥35	0.327	0.254	1.656	0.112	1.387	0.678～21.260
合并高危妊娠		1.549	0.827	3.508	0.020	4.706	2.556～8.665
收缩压(mmHg)		?	?	?	?	?	?
?	≥130～140	0.310	1.308	0.003	0.113	1.363	0.222～15.505
?	≥140～160	0.618	1.083	0.106	0.168	1.855	0.353～19.631
?	≥160	1.691	0.980	8.851	0.085	5.426	0.794～37.069
舒张压(mmHg)		?	?	?	?	?	?
?	≥90～110	0.690	1.351	0.511	0.010	1.993	1.532～17.708
?	≥110	1.865	1.681	1.109	0.047	6.458	2.391～28.166

表4 晚孕期孕妇心力储备指标D/S异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
年龄(岁)		?	?	?	?	?	?
?	≥25～29	0.149	0.350	0.180	0.063	1.160	0.584～2.306
?	≥29～35	－0.018	0.351	0.003	0.050	0.982	0.493～1.957
?	≥35	0.327	0.254	1.656	0.112	1.387	0.678～21.260
合并高危妊娠		1.549	0.827	3.508	0.020	4.706	2.556～8.665
收缩压(mmHg)		?	?	?	?	?	?
?	≥130～140	0.310	1.308	0.003	0.113	1.363	0.222～15.505
?	≥140～160	0.618	1.083	0.106	0.168	1.855	0.353～19.631
?	≥160	1.691	0.980	8.851	0.085	5.426	0.794～37.069
舒张压(mmHg)		?	?	?	?	?	?
?	≥90～110	0.690	1.351	0.511	0.010	1.993	1.532～17.708
?	≥110	1.865	1.681	1.109	0.047	6.458	2.391～28.166

表5 晚孕期孕妇心力储备指标T1/M1异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
孕次(次)		?	?	?	?	?	?
?	2	1.296	0.469	7.634	0.236	3.654	0.429～30.958
?	3	1.462	0.583	6.290	0.825	4.315	0.447～34.779
?	≥4	2.257	1.893	1.421	0.037	9.555	1.147～77.955

表5 晚孕期孕妇心力储备指标T1/M1异常的可能影响因素的分析结果

影响因素		B	SE	Wald值	P值	OR值	OR值95%CI
孕次(次)		?	?	?	?	?	?
?	2	1.296	0.469	7.634	0.236	3.654	0.429～30.958
?	3	1.462	0.583	6.290	0.825	4.315	0.447～34.779
?	≥4	2.257	1.893	1.421	0.037	9.555	1.147～77.955

表6 研究组(n＝65)孕妇的心力储备指标S1/S2、D/S与超声心动图检测的心脏EF，对于诊断孕妇心脏功能的比较(例)

心脏EF	S1/S2			D/S
心脏EF	正常	异常	合计	正常	异常	合计
正常(≥55%)	13	2	15	14	3	17
异常(<55%)	2	48	50	1	47	48
合计	15	50	65	15	50	65

表6 研究组(n＝65)孕妇的心力储备指标S1/S2、D/S与超声心动图检测的心脏EF，对于诊断孕妇心脏功能的比较(例)

心脏EF	S1/S2			D/S
心脏EF	正常	异常	合计	正常	异常	合计
正常(≥55%)	13	2	15	14	3	17
异常(<55%)	2	48	50	1	47	48
合计	15	50	65	15	50	65

表7 研究组(n＝65)孕妇的心力储备指标S1/S2、D/S与常规心电图检查结果，对于诊断孕妇心脏功能的比较(例)

常规心电图	S1/S2			D/S
常规心电图	正常	异常	合计	正常	异常	合计
正常	13	5	18	12	4	16
异常	2	45	47	3	46	49
合计	15	50	65	15	50	65

表7 研究组(n＝65)孕妇的心力储备指标S1/S2、D/S与常规心电图检查结果，对于诊断孕妇心脏功能的比较(例)

常规心电图	S1/S2			D/S
常规心电图	正常	异常	合计	正常	异常	合计
正常	13	5	18	12	4	16
异常	2	45	47	3	46	49
合计	15	50	65	15	50	65

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