Pregnancy Associated Cardiomyopathy

Author Information

Pai K*,  Samant PY**, Khare A***

(* Ex Assistant Professor, ** Professor, *** First Year Resident. Department of Obstetrics and Gynecology, Seth GS Medical College and KEM Hospital, Mumbai, India.)

Abstract

A 21 year old woman presented to emergency medical services on day 3 of spontaneous second trimester abortion and subsequent check curettage. She had complaints of breathlessness, pedal edema and abdominal distension preceding the abortion.  Blood investigations and  echocardiogram  were suggestive of cardiomyopathy due to myocarditis. Cardiac medications including beta blockers, ACE inhibitors and diuretics were started. She symptomatically improved over 1 week.

Introduction

Peripartum cardiomyopathy (PPCM) is a rare dilated cardiomyopathy that causes cardiac failure in women in late pregnancy or early postpartum. Antepartum PPCM is rare. About 90% of the cases are diagnosed in the first two months of the postpartum period. PPCM causes significant morbidity and mortality in both mother and fetus; hence all clinicians and, in particular, emergency physicians should be aware of this disease.  Cardiomyopathy associated with early pregnancy has also been called pregnancy associated cardiomyopathy. 

Case Report

A 21 year old woman who had aborted recently, came to emergency services on day 3 of check curettage with complaints of breathlessness (NYHA grade 2), abdominal distension and bilateral pedal edema since 6 days. She aborted spontaneously at 6 months gestation, which was followed by curettage in a private hospital.  She gave history of blood pressure (BP) reading of 130/90 mm of Hg with no albumen in urine, once during pregnancy for which no medications were given. There was no history of any previous medical or surgical illness. On examination, general condition was stable, vital parameters were normal, there was no murmur on auscultation, bilateral coarse crepitations were present,  jugular venous pressure (JVP) was raised, pedal edema was present. Abdominal examination revealed minimal distension. Uterus was just bulky and non tender, per speculum findings were unremarkable. A 2 D echocardiogram (2D echo) that was done was suggestive of global hypokinesia of the left ventricle, grade 2 diastolic dysfunction with an ejection fraction of less than 30 %.  CPK-MB enzyme level was elevated. Troponin-T was weakly positive. A diagnosis of peripartum cardiomyopathy with probable myocarditis was established on the basis of elevated levels of cardiac markers. She was started on beta blockers, ACE inhibitors and diuretics, inj dobutamine drip, tablet carvedilol and injection furosemide (later converted to tablet furosemide), syrup potassium chloride, tablet spiranolactone, and tablet ramipril. Dosages were titrated as per need. Nebulisation with ipratropium was started. She was also given injection ceftriaxone. She symptomatically improved over one week and a repeat 2D echo showed an ejection fraction of 50 %. Following this, she was discharged on cardiac medications. 

Discussion

PPCM was first described in the 18th century but recognized as a separate clinical entity in 1930 and1971. Demakis et al. described criteria for the diagnosis of PPCM.[1] For diagnosis of PPCM the entity should be seen in the last month of pregnancy or first five months after delivery in patient with no identifiable cause for cardiac failure. There should be no recent history of cardiac disease.  Echo cardiographic finding of severe left ventricular systolic dysfunction, demonstrated by  an ejection fraction of less than 45 % and / or reduced shortening fraction of less than 30 % should be seen. An Indian study showed the incidence of PPCM to be 1 in 1374 live births.[2] PPCM constitutes less then 1 % of all cardiovascular events related to pregnancy.[3] There are multiple risk factors postulated as cause of PPCM which include age over 30 years, multi fetal gestation, multiparity, African descent, maternal cocaine abuse, long term tocolytic therapy and selenium deficiency. Our patient did not have any of the above risk factors. In a series of 123 cases of pregnancy associated cardiomyopathy reported by Elkayam, 23 were before 36 weeks and the earliest was at 17 weeks.[4] Our patient presented around 6 months gestation before pregnancy loss which is very rare.

Though the exact etiology of PPCM is still not known,the following hypotheses are proposed. There is increased susceptibility to viral or autoimmune myocarditis in pregnancy. Raised titres of immunoglobins and other auto antibodies in patients with PPCM are suggestive of abnormal immune response.  Fetal cells enter maternal circulation and remain in circulation without rejection due to weak immunogenic paternal halotype of the chorionic cell. If these cells lodge into the cardiac tissue, it triggers an immune response.[5] Maladaptation to stress of pregnancy; hyperdynamic circulation during pregnancy causing remodeling, thyroid disorder and exaggerated reduction in left ventricular systolic function with stress of gestational hypertension may together contribute to cardiac failure in PPCM. Recent studies implicate the role of a prolactin sub fragment 16-kDa which is cleaved from prolactin due to unbalanced oxidative stress. The 16-kDa can destroy the endothelium and damage the micro circulation in the myocardium, reducing the cardiac function and causing ventricular dilatation.[7] The common symptoms include dyspnea, cough, orthopnea, paroxysmal nocturnal dyspnea and rarely thromboembolic manifestations. The mainstay of investigations includes chest x-ray, electrocardiogram and echocardiography. Cardiac markers, such as Troponin T are  suggested to have prognostic implication. B-type natriuretic peptide (BNP) and N terminal pro – BNP (NT- pro BNP) are recommended by the Heart Failure Association of the ESC Working Group on PPCM.[7] Endomyocardial biopsy may show features of myocarditis, but the decision for biopsy should be taken after discussion with the patient and her family. Viral, bacterial culture, and Coxsackie B titres are done in selected cases. Invasive hemodynamic monitoring shows elevated right and left heart filling pressures with reduced cardiac index.

Management of PPCM is similar to other types of heart failure, apart from concern for the adverse effect of treatment on fetus or breast feeding infant. The aim of therapy in PPCM is to reduce preload, after load and increase the cardiac contractility. These can be achieved by treatment of pulmonary congestion, control of hyper/ hypotension, treatment of cardiac arrhythmias and prevention of thromboembolic events. 

Digoxin and diuretics along with beta-blockers improve left ventricular function in patients of PPCM. ACE inhibitors are the drug of choice in postpartum PPCM. Ventricular arrhythmias should be treated aggressively. Therapy with ionotropes such as dobutamine should be directed by invasive cardiac monitoring. Immunosuppressive therapy may be started after two weeks of standard therapy without response in biopsy proven myocarditis, but still efficacy is unclear. Anticoagulation in PPCM is important as pregnancy itself is a hypercoagulable state, in addition to PPCM with dilatation of heart and turbulent flow of blood. Before delivery, unfractionated or low molecular weight heparin is the choice. In postpartum period warfarin is used.

Occasionally, when medical therapy fails, need for mechanical cardiovascular support (intra-aortic balloon pump, ventricular assisting device) and even cardiac transplant have been reported in the literature.[8]

There is no indication to terminate pregnancy in stable patients. In case of  hemodynamically unstable patients early delivery is recommended.[9,10] Maternal mortality rate is higher in black race, multipara and with LVEF less than 30%. Pregnancy should be avoided if LV ejection fraction is < 25% at diagnosis or with incompletely recovered left heart function.[7] 

Conclusion

Peripartum cardiomyopathy is a rare pregnancy-induced dilated cardiomyopathy, seen in the last month of pregnancy and postpartum period, which makes our case of early onset cardiomyopathy in second trimester a rare one. High index of suspicion is required in women presenting with dyspnea without obvious cause in early pregnancy.

References

1. Demakis JG, Rahimtoola SH, Sutton GC, Meadws WR, Szanto PB, Tobin JR et al. Natural course of peripartum cardiomyopathy. Circulation. 1971;44(6):1053-61. 
2. Pandit V, Shetty S, Kumar A, Sagir A. Incidence and outcome of peripartum cardiomyopathy from a tertiary hospital in South India. Trop Doct. 2009;39(3):168-9.
3. Sliwa K, Damasceno A, Mayosi BM. Epidemiology and etiology of cardiomyopathy in Africa. Circulation. 2005;112(23):3577-834. 
4. Elkayam U, Akhter MW, Singh H, Khan S, Bitar F, Hameed A, et al. Pregnancy-associated cardiomyopathy: clinical characteristics and a comparison between early and late presentation. Circulation. 2005;111(16):2050-5.
5. Murali S, Baldisseri MR. Peripartum cardiomyopathy. Crit Care Med. 2005;33(10 Suppl):S340-6.
6. Hilfiker-Kleiner D, Meyer GP, Schieffer E, Goldmann B, Podewski E, Struman I, et al. Recovery from postpartum cardiomyopathy in 2 patients by blocking prolactin release with bromocriptine. J Am Coll Cardiol. 2007;50(24):2354-5.
7. Sliwa K, Hilfiker-Kleiner D, Petrie MC, Mebazaa A, Pieske B, Buchmann E, et al. Current state of knowledge on aetiology, diagnosis, management, and therapy of peripartum cardiomyopathy: a position statement from the Heart Failure Association of the European Society of Cardiology Working Group on peripartum cardiomyopathy. Eur J Heart Fail. 2010;12(8):767-78.
8. Aziz TM, Burgess MI, Acladious NN, Campbell CS, Rahman AN, Yonan N, et al. Heart transplantation for peripartum cardiomyopathy: a report of three cases and literature review. Cardiovasc Surg. 1999;7(5):565-7.
9. Lee W, Cotton DB. Cardiomyopathy: Current concept and clinical management. Clin Obstet Gynecol. 1989;32(1):54–67. 
10. Biteker M, Kayataş K, Duman D, Turkmen M, Bozkurt B. Peripartum Cardiomyopathy: Current State of Knowledge, New Developments and Future Directions.Curr Cardiol Rev. 2014; 10(4): 317–326.

Citation

Pai K,  Samant PY, Khare A. Pregnancy Associated Cardiomyopathy. JPGO 2017. Volume 4 No.11. Available from: http://www.jpgo.org/2017/11/pregnancy-associated-cardiomyopathy.html