Case Presentation

A 34-year-old pregnant patient (G2,P1. at 18 weeks gestation) was admitted to this hospital with a diagnosis of pulmonary edema (New York Heart Association functional class III). She was evaluated by our Cardiology Clinic and diagnosed as rheumatic mitral stenosis. Echocardiography showed a very fibrotic mitral valve. The mitral orifice area was 1.2cm² and 0.9 cm² with planimetric diameter (Figure 1).

Figure 1

Figure 1: Planimetric mitral valve area was 0.9cm².

And her pulmonary arterial pressure (PAP) was 70mmHg(Figure 2).

Figure 2

Figure 2: Her pulmonary pressure was 70mmHg.

Peak gradient was 31mmHg and mean was 21mmHg. Left atrial and appendicial thrombus, left atrial spontaneous echo-contrast (LASEC), mitral valve excursion, regurgitation were determined also. Echo score was 9.She was in sinus rhythm with pliable valve leaflets without any mitral calcification, mitral regurgitation, left atrial thrombus. There was grade II-III LASEC. Despite optimal doses of medications, her clinical and hemodynamic condition did not normalize over the course of 10 days; she continued to be dyspneic with exertion and to have bouts of acute pulmonary edema, whereas her repeat PAP remained high at 70mmHg. Obstetricians observed that fetal development was within normal limits. After this insufficient medical therapy, urgent Percutaneous Balloon Mitral Valvotomy (PBMV) was considered. The patient was counseled about the perioperative and postoperative risks to herself and the fetus and consented to the procedure. PBMV was performed by our Cardiology Department (Figure 3).

Figure 3

Figure 3: Second stage of PBMV.

Severe mitral insufficiency was occurred during balloon inflation due to chordaes and papillar muscles' ruptures (Figure 4).

Figure 4

Figure 4: Mitral insufficiency during PBMV.

After this procedure, urgent mitral valve replacement was performed. Peroperatively a rupture was determined at 3 cm depth and 1/2 cm to annulus and it was close to anterolateral commissure of mitral leaflet (Figure 5).

Figure 5

Figure 5: Perforation area at mitral anterior leaflet.

Two chordas were raised from the middle segment of leaflet and papillary muscle at the tip of one chorda was included by the ruptured chorda structure (Figure 6).

Figure 6

Figure 6: Perforated chorda with papillary muscle.

A hypertrophic papillary muscle under the posteromedial commissure directly adhered to a wide surface including both anterior and posterior leaflets without chorda and because balloon couldn't open the leaflets due to adherence, it caused rupture(Figure 7).

Figure 7

Figure 7: View of iatrogenic ASD.

Native valve was resected. She expected another baby a bioprosthetic mitral valve (Edwards Lifesciences, size 29mm,model 6625, Porcine Tissue Heart Valve) was replaced. Left atriotomy was closed and a right atriotomy was performed. Iatrogenic ASD was 2-3 cm. over the fossa ovalis and at muscular field level of interatrial septum's central part. It was primarily repaired with 2/0 pledget prolen sutures. On transfer to the intensive care unit, obstetric consultation revealed loss of fetal heart beats and movements and assessed fetal viability by ultrasonography immediately after the operation (Figure 8).

Figure 8

Figure 8: Image of fetal ultrasonography.

Fetus was dead and wasn't expelled from the uterus spontaneously, medical abortion was performed after three days. The hospital stay was 8 days. Postoperatively at the discharge day and after 2 months an echocardiographic investigation was normal.

Discussion

Weiss et al, in their summary of case reports and series found that sudden decompensation, fetal immaturity, and the high hemodynamic load of late pregnancy result in a poor maternal and fetal outcome of cardiovascular procedures during pregnancy (1). Use of high flow rate, high pressure, normothermic cardiopulmonary bypass for the shortest period possible is thought to decrease fetal risk (2). Many investigators reported the maternal mortality between 1.5% and 5% and fetal mortality between 16% and 33% (3). Pulmonary edema has been shown to be the leading cause of maternal death (4). The choice of operative technique is also very important (2). Because of the fetal risk, cardiac surgery has been advised only in extreme emergencies (5). PBMV is associated with lower trauma than cardiac operations, however early restenosis and risk of radiation hazard limits its use during pregnancy and there is a risk of emergency surgical intervention in case of the failure of the procedure (6). As the least invasive method, PBMV has many complications such as cardiac perforation, left to-right shunting at the atrial level due to dilatation of atrial septal puncture. Rarely the defect is large enough to cause right heart failure. Systemic arterial hypotension may occur due to transient occlusion of left ventricular inflow during balloon inflation. In addition all patients are exposed to radiation during the procedure (2). The basic principles for the peroperative management of the gravid patient undergoing cardiac surgery and CPB are identical to those for gravidae requiring any type of surgery; attention to maternal safety, avoidance of teratogenic drugs, avoidance of intrauterine asphyxia, and prevention of preterm labor (5). Assessment of fetal viability and heart rate by ultrasonographic evaluation of the fetus early after surgery is also important (2). If intrauterine death of fetus is detected after the cardiac operation and if the fetus is not expelled from the uterus spontaneously, medical abortion should be performed after two days (2).

Correspondence to

Doç. Dr. Ufuk YETKİN 1379 Sok. No: 9,Burç Apt. D: 13 35220, Alsancak – İZMİR / TURKEY Tel: +90 505 3124906 Fax: +90 232 2434848 e-mail: ufuk_yetkin@yahoo.fr