Pediatr Cardiol 12:184-185, 1991
Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1991
P u l m o n a r y H y p e r t e n s i o n with N e c r o t i z i n g Arteritis S e c o n d a r y to C o n g e n i t a l Mitral S t e n o s i s W.B. Cornell, ~ E. Rosenkranz, z D.S. Moodie, 3 and N.B. Ratliff1 Departments of ~Pathology, 2Thoracic and Cardiovascular Surgery, and 3Cardiology and Pediatric and Adolescent Medicine, The Cleveland Clinic Educational Foundation, Cleveland, Ohio, USA
SUMMARY: A case of congenital mitral stenosis with pulmonary hypertension is presented. The severity and rapid development of the pulmonary vascular changes are unusual, especially for a young child. The case underscores the importance of early detection of correctable congenital heart disease and emphasizes the unpredictability of the time course and severity of irreversible pulmonary hypertension. KEY WORDS: Congenital mitral stenosis--Pulmonary hypertension
Case Report A 26-month-old girl was transferred to the Cleveland Clinic for evaluation of congenital heart disease and worsening congestive heart failure. Although the patient reportedly had a murmur as an infant, previous echocardiographic studies were interpreted as normal. Over the second 12 months of life, however, she experienced episodic syncopal episodes and tired easily. Following a bout of streptococcal pharyngitis, the child developed progressive respiratory distress. Echocardiography revealed a parachute mitral valve with mitral valvular stenosis, severe pulmonary hypertension, and severe right ventricular hypertrophy with minimal right ventricular function. The patient underwent open heart surgery for repair of the mitral valve. The postrepair intraoperative echocardiogram estimated a residual mitral valve gradient of less than 10 mmHg and demonstrated mild to moderate mitral regurgitation. The early postoperative course was complicated by severe, refractory pulmonary hypertension despite hyperventilation, paralysis, and pulmonary vasodilators. Progressive respiratory failure requiring high-pressure ventilation resulted in a right-sided bronchopleural fistula and the patient expired on the 26th postoperative day. Postmortem examination was restricted to the heart and lungs. No pleural effusions were noted; there was adhesion formation in the right pleural cavity. The right and left lungs had normal lobar configurations and weighed 300 and 250 g, respectively. On cut surface both lungs were similar, having a liver-like consistency with yellow-gray areas with indistinct edges. The heart weighed 130 g and had a normal circuit of cardiac chambers, great vessels, and coronary arteries. A persistent left superior vena cava was associated with marked enlargement of the
A d d r e s s offprint requests to: Dr. N.B. Ratliff, Department of Pathology, The Cleveland Clinic Educational Foundation, 9500 Euclid Avenue, Cleveland, OH 44195-5138, USA.
coronary sinus. Left and right atrial hypertrophy was marked. No atrial or ventricular septal defects were noted. The dilated, hypertrophied right ventricle had a thickness of 0.6 cm and approximated in prominence the hypertrophied left ventricle which measured 1.0 cm in thickness. The septal curvature was not reversed. The left ventricular outflow tract was narrowed by closely approximated, shortened, malformed papillary muscles. The short, thick chordae tendinae were fused. The posterior leaflet of the mitral valve consisted of a thin fibrotic rim of tissue; the anterior leaflet was thick and fibrotic. The bicuspid aortic valve had a protruding fibrotic rim at the base of the left cusp. No coarctation of the aorta was present. Histological examination of the formalin-inflated lungs revealed a widespread organizing interstitial fibrosis with multiple areas of infarction. Edema and hemosiderin-laden histiocytes were identified within alveolar spaces. Diffuse pulmonary vascular changes were seen in all lobes of the lung. Small and mediumsized arteries showed severe concentric medial hypertrophy and intimal proliferation, often obliterating the lumina. Glomus-like plexiform lesions consisting of microaneurysmal networks of thin-walled channels branching from adjacent arteries were present (Fig. 1). In addition, arteries frequently showed necrotizing inflammation characterized by transmural necrosis and a transmural polymorphous inflammatory reaction consisting of both acute and chronic inflammatory cells (Fig. 2). These vessels also contained recent fbrin thrombi. Other vessels showed organizing thrombi with recanalization. This overall picture is consistent with Heath-Edwards grade VI pulmonary hypertension [2].
Discussion Severe, irreversible pulmonary hypertension developed rapidly in this young patient due to congenital heart disease that evaded early, accurate diagnosis. The extent of the vascular lesions in secondary pul-
Cornell et al.: Congenital Mitral Stenosis
Fig. 1. Arterial plexiform lesion showing medial hypertrophy and intimal proliferation with budding of glomus-like channels. Plexiform lesions are a histopathological indicator of irreversible pulmonary hypertension. Movat pentachrome stain; original magnification, • Fig. 2. Necrotizing arteritis demonstrating transmural necrosis and inflammatory cell infiltrate. Hematoxylineosin stain; original magnification, • 100.
monary hypertension usually depends on the severity and duration of the obstructive process or the severity of shunt-related elevated flow and pressure, but the rate of progression of the vascular changes with a given cardiac defect is not predictable and may reflect unknown genetic factors [3]. Elimination of the causative disorder can lead to a reversal of the pulmonary hypertension; regression of the vascular lesions, however, may take months to years [1]. Plexiform lesions are irreversible and generally not found in pulmonary venous hypertension with postcapillary obstruction (e.g., mitral stenosis) [4, 5]. Necrotizing arteritis is uncommon in both primary and secondary pulmonary hypertension and is generally associated with the most severe grades of pulmonary hypertension.
185
The importance of early recognition of correctable congenital heart disease before irreversible pulmonary vascular changes occur is emphasized by this case. The cardiac anomalies were not clinically evident at the patient's initial presentation at another institution. Progressive secondary pulmonary hypertension subsequently reached the end-stage of severity with widespread interstitial fibrosis, necrotizing arteritis, pulmonary infarction, and secondary infection. The unusually rapid development of pulmonary hypertension to a degree of severity (grade VI), which is itself unusual for this cardiac anomaly, underscores the fundamental unpredictability of both the rapidity of onset and severity of secondary pulmonary hypertension.
References 1. Edwards WD (1988) Pathology of pulmonary hypertension. Cardiovasc Clin 18:321-359 2. Heath D, Edwards JE (1958) The pathology of hypertensive pulmonary vascular disease. Circulation 18:533-547 3. Rabinovitch M (1988) Problems of pulmonary hypertension in children with congenital cardiac defects. Chest 93(Suppl 3):1195-1265 4. Roberts WC (1986) A simple histologic classification of pulmonary arterial hypertension. Am J Cardiol 58:385-386 5. Wagenvoort CA (1986) Lung biopsy findings in secondary pulmonary hypertension. Heart Lung 15:429-450
Pediatric Cardiology 9 Springer-VerlagNew York Inc. 1991
P u l m o n a r y H y p e r t e n s i o n with N e c r o t i z i n g Arteritis S e c o n d a r y to C o n g e n i t a l Mitral S t e n o s i s W.B. Cornell, ~ E. Rosenkranz, z D.S. Moodie, 3 and N.B. Ratliff1 Departments of ~Pathology, 2Thoracic and Cardiovascular Surgery, and 3Cardiology and Pediatric and Adolescent Medicine, The Cleveland Clinic Educational Foundation, Cleveland, Ohio, USA
SUMMARY: A case of congenital mitral stenosis with pulmonary hypertension is presented. The severity and rapid development of the pulmonary vascular changes are unusual, especially for a young child. The case underscores the importance of early detection of correctable congenital heart disease and emphasizes the unpredictability of the time course and severity of irreversible pulmonary hypertension. KEY WORDS: Congenital mitral stenosis--Pulmonary hypertension
Case Report A 26-month-old girl was transferred to the Cleveland Clinic for evaluation of congenital heart disease and worsening congestive heart failure. Although the patient reportedly had a murmur as an infant, previous echocardiographic studies were interpreted as normal. Over the second 12 months of life, however, she experienced episodic syncopal episodes and tired easily. Following a bout of streptococcal pharyngitis, the child developed progressive respiratory distress. Echocardiography revealed a parachute mitral valve with mitral valvular stenosis, severe pulmonary hypertension, and severe right ventricular hypertrophy with minimal right ventricular function. The patient underwent open heart surgery for repair of the mitral valve. The postrepair intraoperative echocardiogram estimated a residual mitral valve gradient of less than 10 mmHg and demonstrated mild to moderate mitral regurgitation. The early postoperative course was complicated by severe, refractory pulmonary hypertension despite hyperventilation, paralysis, and pulmonary vasodilators. Progressive respiratory failure requiring high-pressure ventilation resulted in a right-sided bronchopleural fistula and the patient expired on the 26th postoperative day. Postmortem examination was restricted to the heart and lungs. No pleural effusions were noted; there was adhesion formation in the right pleural cavity. The right and left lungs had normal lobar configurations and weighed 300 and 250 g, respectively. On cut surface both lungs were similar, having a liver-like consistency with yellow-gray areas with indistinct edges. The heart weighed 130 g and had a normal circuit of cardiac chambers, great vessels, and coronary arteries. A persistent left superior vena cava was associated with marked enlargement of the
A d d r e s s offprint requests to: Dr. N.B. Ratliff, Department of Pathology, The Cleveland Clinic Educational Foundation, 9500 Euclid Avenue, Cleveland, OH 44195-5138, USA.
coronary sinus. Left and right atrial hypertrophy was marked. No atrial or ventricular septal defects were noted. The dilated, hypertrophied right ventricle had a thickness of 0.6 cm and approximated in prominence the hypertrophied left ventricle which measured 1.0 cm in thickness. The septal curvature was not reversed. The left ventricular outflow tract was narrowed by closely approximated, shortened, malformed papillary muscles. The short, thick chordae tendinae were fused. The posterior leaflet of the mitral valve consisted of a thin fibrotic rim of tissue; the anterior leaflet was thick and fibrotic. The bicuspid aortic valve had a protruding fibrotic rim at the base of the left cusp. No coarctation of the aorta was present. Histological examination of the formalin-inflated lungs revealed a widespread organizing interstitial fibrosis with multiple areas of infarction. Edema and hemosiderin-laden histiocytes were identified within alveolar spaces. Diffuse pulmonary vascular changes were seen in all lobes of the lung. Small and mediumsized arteries showed severe concentric medial hypertrophy and intimal proliferation, often obliterating the lumina. Glomus-like plexiform lesions consisting of microaneurysmal networks of thin-walled channels branching from adjacent arteries were present (Fig. 1). In addition, arteries frequently showed necrotizing inflammation characterized by transmural necrosis and a transmural polymorphous inflammatory reaction consisting of both acute and chronic inflammatory cells (Fig. 2). These vessels also contained recent fbrin thrombi. Other vessels showed organizing thrombi with recanalization. This overall picture is consistent with Heath-Edwards grade VI pulmonary hypertension [2].
Discussion Severe, irreversible pulmonary hypertension developed rapidly in this young patient due to congenital heart disease that evaded early, accurate diagnosis. The extent of the vascular lesions in secondary pul-
Cornell et al.: Congenital Mitral Stenosis
Fig. 1. Arterial plexiform lesion showing medial hypertrophy and intimal proliferation with budding of glomus-like channels. Plexiform lesions are a histopathological indicator of irreversible pulmonary hypertension. Movat pentachrome stain; original magnification, • Fig. 2. Necrotizing arteritis demonstrating transmural necrosis and inflammatory cell infiltrate. Hematoxylineosin stain; original magnification, • 100.
monary hypertension usually depends on the severity and duration of the obstructive process or the severity of shunt-related elevated flow and pressure, but the rate of progression of the vascular changes with a given cardiac defect is not predictable and may reflect unknown genetic factors [3]. Elimination of the causative disorder can lead to a reversal of the pulmonary hypertension; regression of the vascular lesions, however, may take months to years [1]. Plexiform lesions are irreversible and generally not found in pulmonary venous hypertension with postcapillary obstruction (e.g., mitral stenosis) [4, 5]. Necrotizing arteritis is uncommon in both primary and secondary pulmonary hypertension and is generally associated with the most severe grades of pulmonary hypertension.
185
The importance of early recognition of correctable congenital heart disease before irreversible pulmonary vascular changes occur is emphasized by this case. The cardiac anomalies were not clinically evident at the patient's initial presentation at another institution. Progressive secondary pulmonary hypertension subsequently reached the end-stage of severity with widespread interstitial fibrosis, necrotizing arteritis, pulmonary infarction, and secondary infection. The unusually rapid development of pulmonary hypertension to a degree of severity (grade VI), which is itself unusual for this cardiac anomaly, underscores the fundamental unpredictability of both the rapidity of onset and severity of secondary pulmonary hypertension.
References 1. Edwards WD (1988) Pathology of pulmonary hypertension. Cardiovasc Clin 18:321-359 2. Heath D, Edwards JE (1958) The pathology of hypertensive pulmonary vascular disease. Circulation 18:533-547 3. Rabinovitch M (1988) Problems of pulmonary hypertension in children with congenital cardiac defects. Chest 93(Suppl 3):1195-1265 4. Roberts WC (1986) A simple histologic classification of pulmonary arterial hypertension. Am J Cardiol 58:385-386 5. Wagenvoort CA (1986) Lung biopsy findings in secondary pulmonary hypertension. Heart Lung 15:429-450
