Dilated Cardiomyopathy: Is it an Entity Specific to Pregnancy? S. Donnelly, S. Blake, P. McKenna, D. Sugrue
Department of Clinical Oncology, Mater Misericordiae Hospital, Dublin 7. calculated by ultrasound was 18%. Diuretic treatment was increased to frusemide 80 mg plus amiloride 20 mg daily. On light microscopic examination of an endomyocardial biopsy there was non-specific variability in myocardial fibre size. Twenty-four hour ambulatory monitoring revealed occasional atrial and ventricular premature beats and sinus tachycardia. She was delivered by elective caesarean section for obstetrical reasons (previous lower segment caesarean section) at 36 weeks gestation of an eight and a half pound healthy male infant. Four days following delivery the patient was returned to the maternity unit, feeling well on frusemide 80 mg plus amiloride 20 mg and a low sodium diet.
Introduction Dilated cardiomyopathy is an uncommon complication of pregnancy. Peripartum cardiomyopathy is the name applied to dilated cardiomyopathy occurring in association with pregnancy. It has not been clearly established whether there is a cardiomyopathy specific to pregnancy or pregnancy merely exacerbates a pre-existing disorder. A postal questionnaire of cardiologists and obstetricians in Ireland suggests an incidence of this condition of one per 60,000 deliveries, approximately one case per year. We report three recent patients with the condition. Case History I A 32 year old female was referred for investigation of congestive cardiac failure 16 weeks following spontaneous vaginal delivery of a nine pound female infant. Her antenatal course had been uneventful. The patient had no previous medical history. The family history was negative for cardiac disease and sudden death. On admission she complained of shortness of breath, progressing to paroxysmal nocturnal dyspnea. On clinical examination she was cyanosed, had an elevated jugular venous pressure, gallop rhythm, bibasal fine crepitations, ankle oedema and tender hepatomegaly. Chest x-ray revealed cardiomegaly with a left effusion. The twelve lead electrocardiograph showed sinus tachycardiawith left bundle branch block. Echocardiography showed dilatation of all cardiac chambers with a left ventricular ejection fraction of 17%. Twenty four hour ambulatory monitoring revealed unifocal premature ventricular contractions with runs of asymptomatic nonsustained ventricular tachycardia. On light microscopic examination of an endomyocardialbiopsythere was non-specific variability in myocardial fibre size. There was no histological evidence of acute myocarditis, amyloid, iron or sarcoid involvement. The patient was treated with digoxin, frusemide, enalapril and warfarin. On review nine months later she was asymptomatic on medication, though cardiomegaly persisted and left ventricular ejection fraction was unchanged.
Case History HI A 26 year old female was referred to the intensive care unit with severe left ventricular failure, two days following delivery by caesarean section at 36 weeks gestation of a healthy male infant. Caesarean section had been performed because of pre-eclamptic toxaemia. At 29 weeks gestation the patient had presented with a one week history of dyspnoea and orthopnoea. Blood pressure of 150/100 had been recorded during pregnancy. Cardiac ultrasound examination confirmed very severe impairment of left and right ventricular function with a left ventricular ejection fraction of 12%. On light microscopic examination of an endomyocardial biopsy there was nonspecific variability in myocardial size as in case history I and II above. Twenty-four hour ambulatory monitoring revealed sinus tachycardia, rare premature ventricular contractions, sixty three pairs and one 4-beat run ofventricular tachycardia. On admission to the intensive care unit she was breathless and cyanosed with a blood pressure of 160/115, sinus tachycardia of 150 beats per minute, bilateral fine crepitations, gallop rhythm and elevated jugular venous pressure. The ECG showed sinus tachycardia. Chest x-ray revealed severe pulmonary oedema. Continuous positive airway pressure with 100% 02 was required to maintain adequate oxygenation. Intensive intravenous diuretics with pre and after load reduction was required over seven days. Twelve days following delivery the patient was discharged to the maternity unit, feeling well, on frusemide 80 mg twice daily, amiloride 10 mg twice daily, captopril 25 mg twice daily. On review recently the patient is well on the above medication.
Case History II A 28 year old female presented at 23 weeks gestation with increasing breathlessness. On clinical examination she had mild mitral regurgitation and normal jugular pressure. Chest x-ray was normal. ECG showed sinus tachycardia. Ultrasound examination of her heart showed a dilated left ventricle and ejection fraction of 28%. Frusemide 40 mg plus amiloride 10 mg were commenced orally. At 30 weeks gestation she complained of increasing breathlessnes and left ventricular ejection fraction as
Discussion Peripartum cardiomyopathy has been defined arbitrarily as dilated cardiomyopathypresenting during the last trimester of pregnancy or within six months of delivery1. The reported incidence varies from one per 20,000
Correspondence: D. Sugrue, Mater Hospital, Dublin 7.
633
I.J.M.S.
634 Donnelly et al.
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Fig. 1 - M mode echocardiogram at the level of the papillary muscles showing increased left ventricular dimensions with impaired global systolic function• Abbreviations: IVS - Interventricular septum PLVW - Posterior left ventricular wall deliveries in U.S. centres to one per hundred deliveries in Zaria, Nigeria z~. The accuracy of some of these reports is questionable however because of the absence of strict diagnostic criteria. In a postal questionnaire survey of cardiologists and obstetricians in Ireland we found an incidence of one per 60,000 deliveries or approximately one per year. Based on the Olmsted county study4 of idiopathic dilated cardiomyopathy in the general population the incidence of dilated cardiomyopathy in Ireland would be 210 per year. Under these circumstances it may well be that cardiomyopathy occurring in the peripartum period is simply a coincidence, a pre-existing disorder being made more manifest by the additional haemodynamic stress of pregnancy. There are no distinct clinical or pathological features that distinguish idiopathic dilated cardiomyopathy from cardiomyopathy presenting in pregnancy. The signs and symptoms of the latter are those of heart failure. The ECG typically reveals non-specific ST and T wave changes though surprisingly the ECG was normal on two of three patients in the present report. On echocardiography the chambers are dilated sometimes with mural thrombus Claims have been made for the existence of a specific peripartum cardiomyopathy. There has been much speculation as to aetiology. Suggested predisposing factors include black race, parity, malnutrition, older age, multiple pregnancy and pre-eclamptic toxaemia. In Zaria, Nigeria the traditional peripartum cleansing rites which involve lying
on baked mud beds and eating dried lake salt lead to volume overload, hypertension and heart failure5. Veille 6 suggested autoimmunity as the cause with placental transfer of autoantibodies. Walsh 7 implicated malnutrition. Midei 8 suggested an autoimmune aetiology with alterations in Tcell expression associated with progesterone predisposing peripartum patients to myocarditis. Melvin 9 reported histological evidence of acute inflammatory myocarditis in three patients with pregnancy related cardiomyopathy who responded clinically to immunosuppressive treatment and speculated that myocarditis was an important "cause" of pregnancy-related cardiomyopathy. Systematic endomyocardial biopsy studies of a large number of women with this disorder have not been performed and thus the aetiological role of myocarditis in this syndrome must remain speculative. In the present study biopsies showed no histological evidence for myocarditis. Furthermore the clinical, echocardiographic features and ambulatory monitoring findings were identical to those found in idiopathic dilated cardiomyopathy unassociated with pregnancy. The prognosis is uncertain. There are few longterm follow-up studies and the literature is highly anecdotal. Occasionally full recovery appears to occur, but that is rare. More commonly peripartum cardiomyopathy behaves like the usual variety of dilated cardiomyopathy where the prognosis is closely related to the severity of left ventricular dysfunction. Dilated cardiomyopathy has a tendency to recur during subsequent pregnancies and may even occur
Vol. 161 No 11
after an intervening normal pregnancy probably due to subclinical left ventricular dysfunction or reactivation of the underlying disease process. Management of pregnancy related dilated cardiomyopathy includes the use of diuretics and digoxin. Warfarin and angiotensin converting enzyme inhibitors are best avoided during pregnancy because of teratogenicity but may be used in the post-partum period as in this report. Though Burch 1° advised strict bed rest for prolonged periods no trial has established its benefit. Furthermore prolonged bed rest increases the risk of thromboembolism and can impose a severe burden on the family. Delivery is usually well tolerated. Caesarean section is reserved for obstetric complications. Haemodynamic monitoring may be helpful with judicious use of intravenous diuretics. Joint management by cardiologist, obstetrician, anaesthetist and paediatrician is recommended with delivery where intensive care facilities are available. Further pregnancy is not advised.
Acknowledgements Dr. K. McGarry, Our Lady's Hospital, Navan, Co. Meath for permission to report the case; Dr. D. McDonald, National
Dilated cardiomyopathy 635 Maternity Hospital, Dublin, for helpful comments and Ms. Evelyn Scanlan, for preparation of manuscript. References 1. tlomans, D. C. Current concepts - l~ripartum cardiomyopathy. N. Engl. J. Med. 1985: 312, 1432-1437. 2. Fillmore, S. J., Parry, E. It. O. The evolution of peripartal heart failure in Zaria, Nigeria. Circulation, 1977: 56, 1058-1061. 3. Davidson, N. McD., Parry, E. H. O. Peripartum heart failure. Quarterly Journal of Medicine, 1978: 47, 431-461. 4. Codd, M., Sugrue, D. D., Gersh, B. J. et al. Epidemiology of idiopathic dilated and hyI~rtrophlc cardiomyopathy. A populauon based study in Olmsted County, Minnesota. 1975-1984. Cxrculation, 1989: 80, 564-572. 5. Davidson, N. McD., Parry, E. H.O. The etiology of pafipartum cardiac failure. American Heart Journal, 1979: 97, 535-536. 6. Veille, J. C. Peripartum cardiomyopathies: A review. Am. J. Obstet. Gynecol. 1984: 148, 805-818. 7. Walsh, J. J., Butch, G. E., Black, Wm. C. et al. Idiopathic cardiomyopathy of the puerl~fium. Circulation, 1965: 32, 19-31. 8. Midei, M. G., DeMent, S. H., Feldman, A. M. et al. Circulation, 1990: 81, 922-928. 9. Melvin, K. R., Richardson, P. J., Olsen, E. G. J. et al. Peripartum cardiomyopathy due to myocarditis. N. Engl. J. Med. 1982: 307, 731-735. 10. Butch, G. E., McDonald, C. D., Walsh, J. J. The effect of prolonged bed rest on post partal cardiomyopathy. Am. Heart J. 1971: 81, 186-201.
Department of Clinical Oncology, Mater Misericordiae Hospital, Dublin 7. calculated by ultrasound was 18%. Diuretic treatment was increased to frusemide 80 mg plus amiloride 20 mg daily. On light microscopic examination of an endomyocardial biopsy there was non-specific variability in myocardial fibre size. Twenty-four hour ambulatory monitoring revealed occasional atrial and ventricular premature beats and sinus tachycardia. She was delivered by elective caesarean section for obstetrical reasons (previous lower segment caesarean section) at 36 weeks gestation of an eight and a half pound healthy male infant. Four days following delivery the patient was returned to the maternity unit, feeling well on frusemide 80 mg plus amiloride 20 mg and a low sodium diet.
Introduction Dilated cardiomyopathy is an uncommon complication of pregnancy. Peripartum cardiomyopathy is the name applied to dilated cardiomyopathy occurring in association with pregnancy. It has not been clearly established whether there is a cardiomyopathy specific to pregnancy or pregnancy merely exacerbates a pre-existing disorder. A postal questionnaire of cardiologists and obstetricians in Ireland suggests an incidence of this condition of one per 60,000 deliveries, approximately one case per year. We report three recent patients with the condition. Case History I A 32 year old female was referred for investigation of congestive cardiac failure 16 weeks following spontaneous vaginal delivery of a nine pound female infant. Her antenatal course had been uneventful. The patient had no previous medical history. The family history was negative for cardiac disease and sudden death. On admission she complained of shortness of breath, progressing to paroxysmal nocturnal dyspnea. On clinical examination she was cyanosed, had an elevated jugular venous pressure, gallop rhythm, bibasal fine crepitations, ankle oedema and tender hepatomegaly. Chest x-ray revealed cardiomegaly with a left effusion. The twelve lead electrocardiograph showed sinus tachycardiawith left bundle branch block. Echocardiography showed dilatation of all cardiac chambers with a left ventricular ejection fraction of 17%. Twenty four hour ambulatory monitoring revealed unifocal premature ventricular contractions with runs of asymptomatic nonsustained ventricular tachycardia. On light microscopic examination of an endomyocardialbiopsythere was non-specific variability in myocardial fibre size. There was no histological evidence of acute myocarditis, amyloid, iron or sarcoid involvement. The patient was treated with digoxin, frusemide, enalapril and warfarin. On review nine months later she was asymptomatic on medication, though cardiomegaly persisted and left ventricular ejection fraction was unchanged.
Case History HI A 26 year old female was referred to the intensive care unit with severe left ventricular failure, two days following delivery by caesarean section at 36 weeks gestation of a healthy male infant. Caesarean section had been performed because of pre-eclamptic toxaemia. At 29 weeks gestation the patient had presented with a one week history of dyspnoea and orthopnoea. Blood pressure of 150/100 had been recorded during pregnancy. Cardiac ultrasound examination confirmed very severe impairment of left and right ventricular function with a left ventricular ejection fraction of 12%. On light microscopic examination of an endomyocardial biopsy there was nonspecific variability in myocardial size as in case history I and II above. Twenty-four hour ambulatory monitoring revealed sinus tachycardia, rare premature ventricular contractions, sixty three pairs and one 4-beat run ofventricular tachycardia. On admission to the intensive care unit she was breathless and cyanosed with a blood pressure of 160/115, sinus tachycardia of 150 beats per minute, bilateral fine crepitations, gallop rhythm and elevated jugular venous pressure. The ECG showed sinus tachycardia. Chest x-ray revealed severe pulmonary oedema. Continuous positive airway pressure with 100% 02 was required to maintain adequate oxygenation. Intensive intravenous diuretics with pre and after load reduction was required over seven days. Twelve days following delivery the patient was discharged to the maternity unit, feeling well, on frusemide 80 mg twice daily, amiloride 10 mg twice daily, captopril 25 mg twice daily. On review recently the patient is well on the above medication.
Case History II A 28 year old female presented at 23 weeks gestation with increasing breathlessness. On clinical examination she had mild mitral regurgitation and normal jugular pressure. Chest x-ray was normal. ECG showed sinus tachycardia. Ultrasound examination of her heart showed a dilated left ventricle and ejection fraction of 28%. Frusemide 40 mg plus amiloride 10 mg were commenced orally. At 30 weeks gestation she complained of increasing breathlessnes and left ventricular ejection fraction as
Discussion Peripartum cardiomyopathy has been defined arbitrarily as dilated cardiomyopathypresenting during the last trimester of pregnancy or within six months of delivery1. The reported incidence varies from one per 20,000
Correspondence: D. Sugrue, Mater Hospital, Dublin 7.
633
I.J.M.S.
634 Donnelly et al.
-'~
"."
:
Nowrn~,. ~992
.
.
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I|11
Fig. 1 - M mode echocardiogram at the level of the papillary muscles showing increased left ventricular dimensions with impaired global systolic function• Abbreviations: IVS - Interventricular septum PLVW - Posterior left ventricular wall deliveries in U.S. centres to one per hundred deliveries in Zaria, Nigeria z~. The accuracy of some of these reports is questionable however because of the absence of strict diagnostic criteria. In a postal questionnaire survey of cardiologists and obstetricians in Ireland we found an incidence of one per 60,000 deliveries or approximately one per year. Based on the Olmsted county study4 of idiopathic dilated cardiomyopathy in the general population the incidence of dilated cardiomyopathy in Ireland would be 210 per year. Under these circumstances it may well be that cardiomyopathy occurring in the peripartum period is simply a coincidence, a pre-existing disorder being made more manifest by the additional haemodynamic stress of pregnancy. There are no distinct clinical or pathological features that distinguish idiopathic dilated cardiomyopathy from cardiomyopathy presenting in pregnancy. The signs and symptoms of the latter are those of heart failure. The ECG typically reveals non-specific ST and T wave changes though surprisingly the ECG was normal on two of three patients in the present report. On echocardiography the chambers are dilated sometimes with mural thrombus Claims have been made for the existence of a specific peripartum cardiomyopathy. There has been much speculation as to aetiology. Suggested predisposing factors include black race, parity, malnutrition, older age, multiple pregnancy and pre-eclamptic toxaemia. In Zaria, Nigeria the traditional peripartum cleansing rites which involve lying
on baked mud beds and eating dried lake salt lead to volume overload, hypertension and heart failure5. Veille 6 suggested autoimmunity as the cause with placental transfer of autoantibodies. Walsh 7 implicated malnutrition. Midei 8 suggested an autoimmune aetiology with alterations in Tcell expression associated with progesterone predisposing peripartum patients to myocarditis. Melvin 9 reported histological evidence of acute inflammatory myocarditis in three patients with pregnancy related cardiomyopathy who responded clinically to immunosuppressive treatment and speculated that myocarditis was an important "cause" of pregnancy-related cardiomyopathy. Systematic endomyocardial biopsy studies of a large number of women with this disorder have not been performed and thus the aetiological role of myocarditis in this syndrome must remain speculative. In the present study biopsies showed no histological evidence for myocarditis. Furthermore the clinical, echocardiographic features and ambulatory monitoring findings were identical to those found in idiopathic dilated cardiomyopathy unassociated with pregnancy. The prognosis is uncertain. There are few longterm follow-up studies and the literature is highly anecdotal. Occasionally full recovery appears to occur, but that is rare. More commonly peripartum cardiomyopathy behaves like the usual variety of dilated cardiomyopathy where the prognosis is closely related to the severity of left ventricular dysfunction. Dilated cardiomyopathy has a tendency to recur during subsequent pregnancies and may even occur
Vol. 161 No 11
after an intervening normal pregnancy probably due to subclinical left ventricular dysfunction or reactivation of the underlying disease process. Management of pregnancy related dilated cardiomyopathy includes the use of diuretics and digoxin. Warfarin and angiotensin converting enzyme inhibitors are best avoided during pregnancy because of teratogenicity but may be used in the post-partum period as in this report. Though Burch 1° advised strict bed rest for prolonged periods no trial has established its benefit. Furthermore prolonged bed rest increases the risk of thromboembolism and can impose a severe burden on the family. Delivery is usually well tolerated. Caesarean section is reserved for obstetric complications. Haemodynamic monitoring may be helpful with judicious use of intravenous diuretics. Joint management by cardiologist, obstetrician, anaesthetist and paediatrician is recommended with delivery where intensive care facilities are available. Further pregnancy is not advised.
Acknowledgements Dr. K. McGarry, Our Lady's Hospital, Navan, Co. Meath for permission to report the case; Dr. D. McDonald, National
Dilated cardiomyopathy 635 Maternity Hospital, Dublin, for helpful comments and Ms. Evelyn Scanlan, for preparation of manuscript. References 1. tlomans, D. C. Current concepts - l~ripartum cardiomyopathy. N. Engl. J. Med. 1985: 312, 1432-1437. 2. Fillmore, S. J., Parry, E. It. O. The evolution of peripartal heart failure in Zaria, Nigeria. Circulation, 1977: 56, 1058-1061. 3. Davidson, N. McD., Parry, E. H. O. Peripartum heart failure. Quarterly Journal of Medicine, 1978: 47, 431-461. 4. Codd, M., Sugrue, D. D., Gersh, B. J. et al. Epidemiology of idiopathic dilated and hyI~rtrophlc cardiomyopathy. A populauon based study in Olmsted County, Minnesota. 1975-1984. Cxrculation, 1989: 80, 564-572. 5. Davidson, N. McD., Parry, E. H.O. The etiology of pafipartum cardiac failure. American Heart Journal, 1979: 97, 535-536. 6. Veille, J. C. Peripartum cardiomyopathies: A review. Am. J. Obstet. Gynecol. 1984: 148, 805-818. 7. Walsh, J. J., Butch, G. E., Black, Wm. C. et al. Idiopathic cardiomyopathy of the puerl~fium. Circulation, 1965: 32, 19-31. 8. Midei, M. G., DeMent, S. H., Feldman, A. M. et al. Circulation, 1990: 81, 922-928. 9. Melvin, K. R., Richardson, P. J., Olsen, E. G. J. et al. Peripartum cardiomyopathy due to myocarditis. N. Engl. J. Med. 1982: 307, 731-735. 10. Butch, G. E., McDonald, C. D., Walsh, J. J. The effect of prolonged bed rest on post partal cardiomyopathy. Am. Heart J. 1971: 81, 186-201.
