Percutaneous balloon mitral valvuloplasty in comparison with open mitral valve commissurotomy for mitral stenosis during pregnancy

Anaesthetic considerations for non-obstetric surgery during pregnancy

Surgery during pregnancy is complicated by the need to balance the requirements of two patients. Under usual circumstances, surgery is only conducted during pregnancy when it is absolutely necessary for the wellbeing of the mother, fetus, or both. Even so, the outcome is generally favourable for both the mother and the fetus. All general anaesthetic drugs cross the placenta and there is no optimal general anaesthetic technique. Neither is there convincing evidence that any particular anaesthetic drug is toxic in humans. There is weak evidence that nitrous oxide should be avoided in early pregnancy due to a potential association with pregnancy loss with high exposure. There is evidence in animal models that many general anaesthetic techniques cause inappropriate neuronal apoptosis and behavioural deficits in later life. It is not known whether these considerations affect the human fetus but studies are underway. Given the general considerations of avoiding fetal exposure to unnecessary medication and potential protection of the maternal airway, regional anaesthesia is usually preferred in pregnancy when it is practical for the medical and surgical condition. When surgery is indicated during pregnancy maintenance of maternal oxygenation, perfusion and homeostasis with the least extensive anaesthetic that is practical will assure the best outcome for the fetus.

Mitral stenosis and pregnancy: Current concepts in anaesthetic practice

The incidence of rheumatic mitral stenosis is grossly reduced in India. Still, among heart disease complicating pregnancy, rheumatic mitral stenosis occupies a greater segment. The unique physiological changes in pregnancy and the pathological impact of mitral stenosis over pregnancy and labour are discussed in detail. A multidisciplinary approach in the diagnosis and management reduces the mortality and morbidity during peripartum. The labour analgesia technique and the evidence-based regional and general anaesthesia techniques are discussed at length in this article.

Pregnancy and pulmonary hypertension

When pulmonary hypertension (PH) occurs in pregnancy, physiologic stress can overwhelm an already strained right ventricle resulting in right ventricular failure and death. Mortality remains unacceptably high (25%-30%). Patients with PH should be counseled to avoid pregnancy. This article discusses the physiologic changes of pregnancy that make it difficult for patients with PH, the pitfalls of transthoracic echocardiography in diagnosing PH in pregnancy, and the historical data regarding mortality. The causes of development of PH during pregnancy are discussed, and the limited data on management of patients with PH who choose to carry their pregnancy to term are reviewed.

Treatment of valvular heart disease during pregnancy for improving maternal and neonatal outcome

BACKGROUND

Valvular heart disease constitutes the majority of all causes of heart disease in pregnancy. In the presence of valvular heart disease, the necessary haemodynamic changes of pregnancy might cause heart failure, leading to severe maternal and fetal morbidity and even mortality. Treatment of valvular heart disease is indicated when patients experience a deterioration of symptoms and in case of a severe valvular lesion. Whether medical therapy or interventional therapy is the optimal treatment for both mother and child is unclear.

OBJECTIVES

To assess effectiveness and adverse effects of the different treatment modalities of valvular heart disease in pregnancy to improve maternal and neonatal outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2011), EMBASE (1980 to 23 March 2011) and the reference lists of background review articles.

SELECTION CRITERIA

Randomised controlled trials, quasi-randomised controlled and cluster-randomised controlled trials comparing medical therapy with percutaneous or surgical intervention for the treatment of valvular heart disease in pregnancy.

DATA COLLECTION AND ANALYSIS

We identified no (randomised) controlled trials to assess the effectiveness and adverse effects of the treatment of valvular heart disease in pregnancy.

MAIN RESULTS

There were no randomised controlled trials, quasi-randomised controlled trials or cluster-randomised trials identified from the search strategy.

AUTHORS' CONCLUSIONS

There is insufficient evidence to define the most effective treatment of valvular heart disease in pregnancy to improve maternal and neonatal outcomes.

Mitral balloon valvuloplasty

Percutaneous mitral balloon valvuloplasty (MBV) was introduced in 1984 by Inoue who developed the procedure as a logical extension of surgical closed commissurotomy. Since then, MBV has emerged as the treatment of choice for severe pliable rheumatic mitral stenosis (MS). With increasing experience and better selection of patient, the immediate results of the procedure have improved and the rate of complications declined. When the reported complications of MBV are viewed in aggregate, complications occur at approximately the following rates: mortality (0-0.5%), cerebral accident (1-2%), mitral regurgitation (MR) requiring surgery (1.6-3%). These complication rates compare favorably to those reported after surgical commissurotomy. Several randomized trials reported similar hemodynamic results with MBV and surgical commissurotomy. Restenosis after MBV ranges from 4% to 70% depending on the patient selection, valve morphology, and duration of follow-up. Restenosis was encountered in 31% of the author's series at mean follow-up 9 ± 5.2 years (range 1.5-19 years) and the 10, 15, and 19 years restenosis-free survival rates were (78 ± 2%) (52 ± 3%) and (26 ± 4%), respectively, and were significantly higher for patients with favorable mitral morphology (MES ⩽ 8) at 88 ± 2%, 67 ± 4% and 40 ± 6%), respectively (P < 0.0001). The 10, 15, and 19 years event-free survival rates were (88 ± 2%, 60 ± 4% and 28 ± 7%, respectively, and were significantly higher for patients with favorable mitral morphology (92 ± 2%, 70 ± 4% and 42 ± 7%, respectively (P < 0.0001). The effect of MBV on severe pulmonary hypertension, concomitant severe tricuspid regurgitation, left ventricular function, left atrial size, and atrial fibrillation are addressed in this review. In addition, the application of MBV in specific clinical situations such as in children, during pregnancy and for restenosis is discussed.

The role of catheter balloon commissurotomy for severe mitral stenosis in pregnancy

Mitral stenosis is one of the more commonly seen valve lesions encountered in pregnancy. The pathophysiologic implications, management strategies, and a comprehensive review of literature over the past 20 years for optimal timing of catheter balloon commissurotomy during pregnancy are discussed. Mechanical relief of obstruction is indicated for cases of severe symptomatic mitral stenosis in pregnancy refractory to medical therapy. Catheter balloon commissurotomy is the procedure of choice in a select group of these patients with suitable valve morphology.

Mitral stenosis

Mitral stenosis is a common disease that causes substantial morbidity worldwide. The disease is most prevalent in developing countries, but is increasingly being identified in an atypical form in developed countries. All treatments that increase valve area improve morbidity. Mortality improves with surgery; the benefit of percutaneous balloon valvuloplasty to mortality might be similar to that of surgery but needs further study. Percutaneous balloon valvuloplasty is the treatment of choice for patients in whom treatment is indicated, except for those with suboptimum valve morphology, and even these patients are sometimes treated with this procedure if surgery is not feasible or if surgical risk is prohibitive. We review the pathology, diagnosis, and treatment options for patients with mitral stenosis.

Mitral valve disease in pregnancy: outcomes and management

Young women may have asymptomatic mitral valve disease which becomes unmasked during the haemodynamic stress of pregnancy. Rheumatic mitral stenosis is the most common cardiac disease found in women during pregnancy. The typical increased volume and heart rate of pregnancy are not well tolerated in patients with more than mild stenosis. Maternal complications of atrial fibrillation and congestive heart failure can occur, and are increased in patients with poor functional class and severe pulmonary artery hypertension. Patients can be diagnosed by echocardiography and symptoms treated with beta-1 antagonists and cautious diuresis. Patients with heart failure unresponsive to treatment can undergo percutaneous balloon mitral valvuloplasty. Labour and delivery goals include reducing tachycardia by adequate pain control and minimized volume shifts. Mitral valve regurgitation, even when severe, is usually very well tolerated in pregnancy as the increase in volume is offset by a decrease in vascular resistance. On the other hand, patients with left ventricular dysfunction, moderate pulmonary hypertension or NYHA functional class III-IV are at increased risk for heart failure and arrhythmias. They may need cautious diuresis and limitations on physical activity during pregnancy, as well as invasive haemodynamic monitoring for labour and delivery. Vaginal delivery is preferred and caesarean section reserved for obstetric indications.

[Pregnancy and heart disease]

Pregnancy and delivery are associated with substantial physiological changes that require adaptations in the cardiovascular system. These changes, well-tolerated in pregnant women without heart disease, expose woman with cardiovascular disease to serious risk. In fact, heart disease is the most frequent cause of maternal death, after psychiatric disorders, and the number of pregnant women with heart disease is expected to grow in the coming years. Preventing cardiovascular complications should be the main aim of every cardiologist involved in managing pregnant woman with congenital or acquired heart disease. Unfortunately, there is a lack of data which would help in the management of these patients during pregnancy and the clinical practice guidelines are often based on assumptions regarding how a specific substrate is going to respond to the physiological changes occurring due to pregnancy.

Percutaneous mitral balloon valvotomy

Percutaneous mitral balloon valvotomy (PMBV) was introduced in 1984 by Inoue who developed the procedure as a logical extension of surgical closed commissurotomy. Since then, PMBV has emerged as the treatment of choice for severe pliable rheumatic mitral stenosis (MS). With increasing experience and better selection of patient, the immediate results of the procedure have improved and the rate of complications declined. When the reported complications of PMBV are viewed in aggregate, complications occur at approximately the following rates: mortality (0-0.5%), cerebral accident (0.5-1%), mitral regurgitation (MR) requiring surgery (1.6-3%). These complication rates compare favorably to those reported after surgical commissurotomy. Several randomized trials reported similar hemodynamic results with PMBV and surgical commissurotomy. Restenosis after PMBV ranges from 4 to 70% depending on the patient selection, valve morphology, and duration of follow up. Restenosis was encountered in 21% of the author's series at mean follow-up 6 +/- 4.5 years and the 10 and 15 years restenosis-free survival rates were (70 +/- 3)% and (44 +/- 5)%, respectively, and were significantly higher for patients with favorable mitral morphology (85 +/- 3% and 65 +/- 6%), respectively (P < 0.0001). The 10 and 15 years event-free survival rates were (79 +/- 2)% and (43 +/- 9)% and were significantly higher for patients with favorable mitral morphology (88 +/- 2)% and (66 +/- 6)%, respectively (P < 0.0001). The effect of PMBV on severe pulmonary hypertension, concomitant severe tricuspid regurgitation, left ventricular function, left atrial size, and atrial fibrillation are addressed in this review. In addition, the application of PMBV in specific clinical situations such as in children, during pregnancy and for restenosis is discussed.

Immediate and long-term follow-up of percutaneous balloon mitral valvuloplasty in pregnant patients with rheumatic mitral stenosis

Percutaneous mitral balloon valvuloplasty (PMV) can be performed during pregnancy without significant maternal risk or fetal morbidity or mortality. However, little is known about long-term follow-up results after PMV in populations of pregnant women. Thus, the present study was undertaken to determine the immediate and long-term outcomes after PMV in a large cohort of pregnant patients with severe mitral stenosis. The patient population consisted of 71 consecutive pregnant women with severe rheumatic mitral stenosis admitted to the hospital with severe congestive heart failure (New York Heart Association class III and IV) for PMV. All patients underwent clinical and obstetric evaluations, electrocardiography, and 2-dimensional and Doppler echocardiography. PMV was successful in all patients, resulting in a significant increase in mitral valve area from 0.9 +/- 0.2 to 2.0 +/- 0.3 cm2 (p <0.001). At the end of pregnancy, 98% of the patients were in New York Heart Association functional class I or II. At a mean follow-up of 44 +/- 31 months, the total event-free survival rate was 54%. The mean gestational age at delivery time was 38 +/- 1 weeks. Preterm deliveries occurred in 9 patients (13%), including 2 twin pregnancies. The remaining 66 of 75 newborns (88%) had normal weight (mean 2.8 +/- 0.6 kg) at delivery. At long-term follow-up of 44 +/- 31 months after birth, the 66 children exhibited normal growth and development and did not show any clinical abnormalities. In conclusion, PMV is safe and effective, has a low morbidity and mortality rate for the mother and the fetus, and has favorable long-term results in pregnant women with rheumatic mitral stenosis in New York Heart Association functional class III or IV.

Valvular heart disease in pregnancy

Women with valvular disease who are pregnant or planning to conceive require careful evaluation and management. Pregnancy is associated with normal physiologic changes that can aggravate many valvular conditions and may require the initiation or increase of cardiovascular medications to manage fluid overload or arrhythmias. Most women will tolerate pregnancy and delivery without major complication, though some types of valvular heart disease are poorly tolerated and require more intensive management, or even termination of the pregnancy. In addition, patients at risk of thromboembolism and those who have prosthetic cardiac valves require anticoagulation. The decision regarding the choice and intensity of anticoagulation requires careful balance between the individual risks of thrombosis and bleeding in the mother and harm to the fetus.

The clinical and hemodynamic results of mitral balloon valvuloplasty for patients with mitral stenosis complicated by severe pulmonary hypertension

BACKGROUND

Percutaneous balloon mitral valvuloplasty (PBMV) has become the procedure of choice for isolated, uncomplicated mitral stenosis (MS) with favorable morphology and may be a useful method for surgical high-risk conditions such as advanced age, the presence of severe tricuspid regurgitation, New York Heart Association (NYHA) class IV at presentation, and severe pulmonary hypertension (PH). The development of PH is a common and important sequela in patients with advanced mitral stenosis and is associated with hemodynamic and clinical decompensation. However, the influence of PBMV on patients with severe PH has seldom been evaluated. Our objective was to probe into the immediate and long-term effects of PBMV on patients with MS complicated by severe PH and to predict the factors that determine the prognosis of patients with severe PH.

METHODS

We included 44 patients with MS complicated by severe PH (systolic pulmonary pressure >80 mm Hg, group S) and 67 patients with MS complicated by mild PH (systolic pulmonary pressure <50 mm Hg, group M) in this study and we compared their immediate and late results after a follow-up period of 24 months after PBMV.

RESULTS

Compared with group M, patients in group S were older, presented more frequently with NYHA III-IV class, valvular echo score >or=8, and more severe tricuspid regurgitation, and had a bigger left atrial diameter before PBMV. The successful rate and the incidence of severe complications from the PBMV procedure were similar in both groups. There were more cases of post-PBMV mitral valve area >or=1.5 cm(2) in group M than in group S, and the average mitral valve area in group M was somewhat larger than that of group S. After PBMV, NYHA class obviously improved in both groups, but there were more patients with NYHA<or=class II in group M than in group S at discharge. During the 24-month follow-up, 7 patients (10.5%) in group M and 11 (25.0%) in group S developed cardiac events (p<0.1). Cumulative event-free survival was 89.6% in group M and 75.0% in group S (p>0.05). NYHA class I or II was present for 80.6% in group M and 59.1% in group S (p<0.10).

RESULTS

PBMV is a safe and effective procedure for patients with severe PH. It can remarkably improve clinical outcomes, although hemodynamic effects of PBMV on this subgroup are not complete. Pre-existing older age, more severe valvular lesion and tricuspid regurgitation, worse cardiac function, and bigger left atrial size in patients with severe PH may be important risk factors for the poor hemodynamic outcomes of PBMV.

Severe cardiac disease in pregnancy, part II: impact of congenital and acquired cardiac diseases during pregnancy

PURPOSE OF REVIEW

Part II of this review gives an overview of the different maternal cardiac problems during pregnancy and their management, and developments over recent years.

RECENT FINDINGS

Many studies published over the last 5 years provided new insights on different cardiac diseases in pregnancy. Publications discussed in this part of the review on cardiac disease in pregnancy, for example, provide epidemiological data on heart disease during pregnancy in general, and cardiomyopathy and ischemic heart disease in particular. In addition, we discussed the implications of a history of peripartum cardiomyopathy for a subsequent pregnancy, interventional strategies during pregnancy in women with ischemic heart disease, and the role of echocardiography in the evaluation of cardiac disease in pregnancy.

SUMMARY

The prevalence of the different causes of heart disease has shifted towards congenital heart disease by the end of the millennium. In developing countries, relatively rare diseases like rheumatic fever are still common, so these diseases are increasingly 'exported' to developed countries. The group of women with congenital heart disease represents most women with heart disease during pregnancy, followed by rheumatic heart disease. With the exception of patients with Eisenmenger's syndrome, pulmonary vascular obstructive disease, and Marfan's syndrome with aortopathy, maternal death during pregnancy is rare in women with heart disease. Although the risk for mortality is low in pregnant women with preexistent cardiac disease, these women are at increased risk for serious morbidity such as heart failure, arrhythmias, and stroke.

Valvular Heart Disease and Pregnancy

Pregnancy in patients with valvular heart disease (VHD) continues to pose a challenge to both physicians and their patients and could be associated with an unfavorable maternal as well as fetal outcome. The purpose of this paper is to review the available clinical data and provide recommendations for the management of patients with VHD during gestation.

Long-term outcome of patients undergoing balloon mitral valvotomy in pregnancy

The outcome of 36 patients (mean age 25.8 +/- 4.3 years) who underwent balloon mitral valvuloplasty during pregnancy is described in this report. The procedure was successful in 35 patients (97.2%), with no maternal mortality, and all patients subsequently had symptomatic improvement and uneventful deliveries. The children had normal growth and development at a follow up of 2.8 +/- 3.3 years. Thus, in patients with symptomatic severe mitral stenosis, balloon mitral valvuloplasty is feasible, safe, and effective with good long-term outcomes for both the mother and the fetus.

Cardiac disease in pregnancy

This article reviews the complications, management and prognosis of cardiac disease in pregnancy.

[Mitral stenosis]

The decrease in the incidence of acute rheumatic fever in western countries has led to a sharp decrease in the incidence of mitral stenosis. This decrease also modifies the clinical presentation and mitral stenosis is now encountered in older patients who have severe impairment of valve anatomy. In developing countries, mitral stenosis remains a frequent disease. The management of patients with mitral stenosis has been modified by the development of percutaneous mitral commissurotomy whose safety and efficacy have been demonstrated in a number of studies with a follow-up of up to ten years. Percutaneous mitral commissurotomy is now the reference treatment for mitral stenosis with pliable valves in young patients and its efficacy has been validated in randomised trials versus surgery. Mitral stenosis in older patients, as it is encountered in western countries, is a more heterogeneous group. Predictive analysis has shown that the predictions of immediate and late results are multifactorial. This has led to consider the indications for percutaneous mitral commissurotomy in patients who do not have ideal anatomic conditions, when their other characteristics are favourable. This is particularly the case in young patients who do not have a very tight mitral stenosis (1-1.5 cm2) and who do not have an advanced heart disease. When the conditions are favourable, percutaneous mitral commissurotomy can be considered in patients who have few symptoms, in particular in order to reduce the thromboembolic risk.

The pregnant cardiac woman

Cardiac diseases are present in 0.5-4% of pregnancies, and they remain a frequent cause of death during pregnancy. Pregnancy per se imposes significant hemodynamic changes, placing a major burden on the cardiovascular system. The early recognition and close follow-up of patients with cardiac diseases will improve maternal tolerance to the cardiovascular burden imposed by pregnancy, promote fetal growth and neonatal survival. Rheumatic heart disease remains the most frequent heart disease in the pregnant population with pulmonary edema as the most frequent complication. Atrial septal defect is the most frequent congenital heart disease in the adult population, whereas tetralogy of Fallot is the most common cyanotic congenital heart disease. An improvement in modern techniques of monitoring, a better understanding of the pathophysiology of cardiac disease, as well as multidisciplinary care has led to a substantial improvement in outcome of the pregnant cardiac patient. Management should be initiated before conception as it will provide optimal clinical conditions and sufficient information on the underlying pathophysiology.

The long-term outcome of balloon valvuloplasty for mitral stenosis

Percutaneous mitral commissurotomy (PMC) is the treatment of choice in young patients who have favorable valve anatomy. It affords an event-free survival greater than 90% at 5 to 7 years,. Economic considerations are the main limitation of PMC in such patients, who are mainly encountered in developing countries. Mitral stenosis in older patients with less favorable valve anatomy is the most frequent presentation in Western countries. This represents a heterogeneous group, but predictive analyses are helpful in deciding who should have PMC. The main conclusion is that the prediction of immediate and late results is multifactorial. Good results can be expected in young patients with unfavorable valve anatomy who do not have a very tight stenosis, are moderately symptomatic, and in sinus rhythm. In addition, PMC may reduce the thromboembolic risk related to mitral stenosis.

Effect of electrical stimulus parameters on the development and propagation of action potentials in short excitable fibres

Intracellular action potentials (IAPs) produced by short fibres in response to their electrical stimulation were analysed. IAPs were calculated on the basis of the Hodgkin-Huxley (1952) model by the method described by Joyner et al. (1978). Principal differences were found in processes of activation of short (semilength L less than 5 lambda) and long fibres under near-threshold stimulation. The shorter the fibre, the lower was the threshold value (Ithr). Dependence of the latency on the stimulus strength (Ist) was substantially non-linear and was affected by the fibre length. Both fibre length and stimulus strength influenced the IAP amplitude, the instantaneous propagation velocity (IPV) and the site of the first origin of the IAP (and, consequently, excitability of the short fibre membrane). With L less than or equal to 2 lambda and Ithr less than or equal to Ist less than or equal to 1.1Ithr, IPV could reach either very high values (so that all the fibre membrane fired practically simultaneously) or even negative values. The latter corresponded to the first origin of the propagated IAP, not at the site of stimulation but at the fibre termination or at a midpoint. The characters of all the above dependencies were unchanged irrespective of the manner of approaching threshold (variation of stimulus duration or its strength). Reasons for differences in processes of activation of short and long fibres are discussed in terms of electrical load and latency. Applications of the results to explain an increased jitter, velocity recovery function and velocity-diameter relationship are also discussed.