Heart disease in pregnancy is a serious complication of obstetrics. It is still the main cause of maternal death, ranking second only to postpartum hemorrhage, and is also the first cause of non-direct obstetric death, so it should be given full attention. The ratio of rheumatic heart disease to congenital heart disease has decreased from 20:1 in the 1950s to 1:1 or 1:2 at present, and according to the latest statistics, congenital heart disease accounts for 35% to 50% of the patients with combined heart disease in pregnancy. In addition to congenital heart disease and wind heart disease, there are also hypertensive heart disease in pregnancy, anemic heart disease, other such as pulmonary heart disease, myocarditis, cardiomyopathy, hypertensive heart disease, etc.
Due to its unique hemodynamic characteristics, there are three most dangerous periods in the perinatal period: the 32nd to 34th week of pregnancy, the delivery period and the three days after delivery (early puerperium). In particular, the delivery period is the period of heaviest cardiac burden, when pregnant women with heart disease are very vulnerable to heart failure. Heart failure is the main cause of death in pregnant women with heart disease.
Diagnostic points.
I. Diagnosis of heart disease.
1.History of palpitations, shortness of breath, heart failure before pregnancy, or history of rheumatic fever, physical examination, X-ray, ECG examination had been diagnosed with organic heart disease.
2.There are clinical symptoms such as exertional dyspnea, frequent nocturnal telangiectatic breathing, hemoptysis, and frequent chest tightness and chest pain.
3. There was cyanosis, pestle finger, and persistent jugular vein anger. There is diastolic grade 2 or more or rough all-systolic grade 3 or more murmur on cardiac auscultation. There is pericardial friction sound, diastolic gallop rhythm or alternating pulse.
4. The electrocardiogram has severe arrhythmias, such as atrial fibrillation,. Atrial flutter, Ⅲ degree AV block, abnormal ST segment and T wave changes, etc.
5.X-ray examination shows significant enlargement of the heart, especially the enlargement of individual heart chambers. Echocardiography shows myocardial hypertrophy, abnormal valve movement, and abnormal intracardiac structures.
Second, heart function grading of pregnant women with heart disease
According to the New York Heart Association (NYHA), the cardiac function of pregnant women with heart disease is graded according to the patient’s ability to live (functional capcity) as follows.
Grade Ⅰ: general physical activity is not limited
Grade Ⅱ: general physical activity is mildly restricted, palpitations and mild shortness of breath after activity, no symptoms at rest.
Grade Ⅲ: general physical activity is obviously restricted, no discomfort at rest, symptoms such as palpitations and dyspnea with mild daily work, or a history of heart failure in the past.
Class IV: Severely limited in general physical activity, unable to perform any physical work, with palpitations, dyspnea and other manifestations of heart failure at rest.
The New York Heart Association (NYHA) classifies heart disease based on objective examination means (ECG, stress test, X-ray, echocardiography, etc.) as follows.
Class A:No objective basis for cardiovascular disease.
Grade B: Objective examination indicates that the patient belongs to mild cardiovascular disease.
Grade C: Objective examination indicates a patient with moderate cardiovascular disease.
Grade D: Objective examination shows that the patient is a patient with severe cardiovascular disease.
Early heart failure performance.
1. Chest tightness, palpitations and shortness of breath after light activity.
2.Heart rate >110 beats/minute and respiration >20 beats/minute at rest.
3, often need to sit up and breathe at night due to chest tightness, walk to the window to breathe fresh air.
4.A small amount of persistent wet rales appear at the bottom of the lungs, which do not disappear after coughing.
Pre-pregnancy counseling.
Pre-pregnancy counseling for patients with heart disease is very important to determine the ability to tolerate pregnancy based on the type of heart disease, the degree of lesion, whether surgical correction is required, the level of cardiac function and medical conditions, etc.
The patient can be pregnant if the heart lesion is mild, the heart function is grade I-II, there is no previous history of heart failure, and there are no other complications.
Pregnancy is not possible for those with severe heart lesions, cardiac function grade III-IV, previous history of heart failure, pulmonary hypertension, right-to-left shunt congenital heart disease, severe arrhythmia, active rheumatic fever, heart disease complicated by bacterial endocarditis, acute myocarditis, etc. Heart failure is very likely to occur during pregnancy and pregnancy is not recommended. In particular, those who are over 35 years old and have a long history of heart disease have a high possibility of heart failure and should not be pregnant.
Treatment principles.
I. Pregnancy period.
1, decide whether to continue the pregnancy: all pregnant women with heart disease who are not suitable for pregnancy should have a therapeutic abortion before 12 weeks of gestation. If the pregnancy has exceeded 12 weeks of gestation, close monitoring should be done to strengthen prenatal checkups and actively prevent and treat heart failure to get through the pregnancy and delivery period. For cases of intractable heart failure, in order to reduce the burden on the heart, a cesarean section should be performed under close supervision in cooperation with an internist.
2. Strengthen prenatal checkups: every 2 weeks before 20 weeks of pregnancy and once a week after 20 weeks. If early signs of heart failure are found, you should be hospitalized immediately. Those who have a smooth pregnancy should also be hospitalized at 36-38 weeks of gestation.
3. Prevention and treatment of heart failure
(1) Rest Ensure rest, sleep more than 10 hours per night, avoid overwork and emotional excitement.
(2) Diet Limit excessive weight gain due to excessive nutrition. Weight gain should not exceed 0.5kg per month, and no more than 12kg during the whole pregnancy is appropriate. Ensure a reasonable amount of high protein, vitamins and iron supplements. Limit salt appropriately, usually no more than 4 to 5g per day.
(3) Prevention and treatment of triggers causing heart failure: 1) prevention of upper respiratory tract infection; 2) correction of anemia; 3) treatment of cardiac arrhythmias; 4) prevention and treatment of hypertensive disorders of pregnancy or other comorbidities and complications.
(4) Dynamic observation of cardiac function: 1) regular echocardiography; 2) determination of cardiac ejection fraction, expulsion per minute, cardiac expulsion index and ventricular wall motion status.
(5) Treatment of heart failure: 1) Hemodilution, increased blood volume and increased glomerular filtration rate in pregnant women during pregnancy make the drug concentration in the blood of pregnant women lower, but at the same time pregnant women tolerate digitalis drugs less well, so it is not appropriate to prevent the use of digitalis drugs. 2) If heart failure occurs in late pregnancy, the principle is to do obstetric treatment after heart failure is controlled, and the indications for cesarean section should be relaxed. 3) If it is severe 3) If the heart failure is severe and the medical treatment is not effective, emergency cesarean delivery can be performed while controlling the heart failure to remove the fetus and reduce the heart burden in order to save the life of the pregnant woman.
Early heart failure or heart function class IV. Digoxin 0.25mg orally twice daily; change to 0.25mg Qd after 2-3d, do not use saturation amount for resuscitation.
Second, during labor and delivery.
1. Indications and management of vaginal delivery.
1) Indications for vaginal delivery.
① Heart function grade Ⅰ to Ⅱ, no previous history of heart failure.
②The fetus is not large, normal fetal position, no abnormal bone and soft birth canal and good cervical maturity.
③No obstetric complications.
2) Treatment of vaginal delivery.
(1) First stage of labor.
(1) The first stage of labor: ① Comfort and encourage the mother, eliminate the tension;
②Oxygen, appropriate application of sedatives such as diazepam, pethidine;
③Check blood pressure, pulse, respiration, heart rate, and record urine volume and lung auscultation every hour;
④When there is early manifestation of heart failure, take semi-recumbent position, high concentration mask oxygen, and give rapid Cetiran 0.4mg + 25% glucose 20ml, slowly sedated. If necessary, repeat the drug once in 4-6 hours;
(5) Give antibiotics to prevent infection as soon as the labor process starts.
(2) Second stage of labor: avoid holding the breath and adding abdominal pressure, perform posterior-lateral perineal incision, fetal head suction or low forceps to assist delivery, and shorten the second stage of labor as much as possible.
(3)The third stage of labor.
① Once the fetus is delivered, press the sandbag on the mother’s abdomen;
② Intravenous or intramuscular injection of 10 to 20 units of contraction, ergot is prohibited;
③ When the mother bleeds excessively, blood and fluid should be transfused in time, but be careful not to infuse too fast.
2. Indications for cesarean delivery and treatment.
1) Indications for cesarean delivery
①History of heart failure in the past and during pregnancy, or heart function grade III-IV, elective cesarean delivery should be performed at the appropriate time after heart failure control.
②Cyanotic precordial disease.
③Cesarean section should be performed for those with pulmonary stasis on chest X-ray (early heart failure) even if the heart function is grade Ⅰ to Ⅱ.
④High-age primiparous delivery.
⑤ Those with obstetrical and other medical comorbidities, and those with large breech fetuses also belong to the next category.
2) Treatment of cesarean delivery.
①Anesthesia: continuous epidural anesthesia, epinephrine should not be added to the anesthetic, and the level of anesthesia should not be too high.
② Rehydration: intraoperative and postoperative rehydration should be strictly limited to the total 24-hour intake.