Cardiovascular Involvement in Systemic Diseases

A

Description

This syndrome, formerly known as DiGeorge syndrome, occurs in both males and females. These patients have a deletion of the long arm of chromosome 22 (22q11.2) detectable with the fluorescence in situ hybridization (FISH) technique.

B

Clinical Manifestations

Clinical features of the syndrome are collectively grouped under the acronym of CATCH-22 ( c ardiac, a bnormal facies, t hymic hypoplasia, c left palate, and h ypocalcemia resulting from 22 q11 deletion).

• 1.

  C ardiac. The great majority of patients (85%) with the syndrome have serious CHDs. The common ones include TOF (25%), interrupted aortic arch (15%), VSD (15%), persistent truncus arteriosus (9%), and isolated aortic arch anomalies (5%).

• 2.

  A bnormal facies: hypertelorism, micrognathia, short philtrum with fish mouth appearance, antimongoloid slant, telecanthus with short palpebral fissures, and low-set ears, often with defective pinna.

• 3.

  T hymic hypoplasia or aplasia, with mild to moderate decrease in T-cell number.

• 4.

  C left: anomalies in the palate (70% to 80%) with speech and feeding disorders.

• 5.

  H ypocalcemia (60%) is due to hypoparathyroidism.

• 6.

  General. Short stature, mental retardation, and hypotonia in infancy are frequent. Occasionally, psychiatric disorders (e.g., schizophrenia and bipolar disorder) develop.

C

Management

• 1.

  Correction of cardiac malformation is required; cardiac defects are major causes of early death.

• 2.

  Irradiated, cytomegalovirus-negative blood products must be administered because of the risk of graft-versus-host disease with nonirradiated products.

• 3.

  Monitoring of serum calcium levels and supplementation of calcium and vitamin D are important.

  • a.

    Calcium gluconate, 500 to 750 mg/kg/day, PO, every 6 hours, or calcium carbonate, 50 to 150 mg/kg/day, PO, every 6 hours.

  • b.

    Ergocalciferol (vitamin D ₂ ), 25,000 to 200,000 U PO QD.

• 4.

  Live vaccines are contraindicated in patients with 22q11 deletion syndrome and in household members because of the risk of shedding live organisms.

• 5.

  Early thymus transplantation may promote successful immune reconstitution.

A

Description

This autosomal recessive disease manifests with the onset of ataxia usually before age 10 years and progresses slowly, involving the lower extremities to a greater extent than the upper extremities. Explosive dysarthric speech and nystagmus are characteristic, but intelligence is preserved.

B

Cardiovascular Manifestations

• 1.

  Cardiomyopathy is found in approximately 30% of the cases. Hypertrophic cardiomyopathy with normal LV systolic function is the most common finding. In advanced stage, the LV enlarges, the LV wall thickness decreases, and LV systolic function decreases. CHF is the terminal event, with most patients dying before age 40 years.

• 2.

  The electrocardiogram (ECG) may show the T vector change in the limb leads or left precordial leads. Occasionally, LVH, RVH, abnormal Q waves, or short PR intervals are found.

C

Management

The same as described for cardiomyopathy.

A

Description

• 1.

  Hyperthyroidism results from excess production of T ₃ (triiodothyronine), T ₄ (thyroxine), or both. The level of thyroid-stimulating hormone (TSH) is suppressed.

• 2.

  The actions of thyroid hormone on the CV system include (a) increasing heart rate, cardiac contractility, and cardiac output; (b) increasing systolic pressure and decreasing diastolic pressure, with mean pressure unchanged; and (c) increasing myocardial sensitivity to catecholamines.

B

Clinical Manifestations

• 1.

  Congenital hyperthyroidism (neonatal Graves disease): an anxious, irritable, and unusually alert baby with widely open eyes (exophthalmic). Many of the infants are premature and most have goiters.

• 2.

  Children with juvenile hyperthyroidism (Graves disease) are hyperactive, irritable, and excitable. The patients have exophthalmos and a goiter. There is a 5:1 female-to-male ratio.

• 3.

  Cardiovascular manifestations include tachycardia, full and bounding pulses, and increased systolic and pulse pressures. Bruits may be audible over the enlarged thyroid in children but not in newborns. In severely affected patients, cardiac enlargement and cardiac failure may develop.

• 4.

  Chest radiographs usually are normal unless CHF develops.

• 5.

  The ECG may show sinus tachycardia, peaked P waves, various arrhythmias (SVT, junctional rhythm), complete heart block, RVH, LVH, or biventricular hypertrophy.

• 6.

  Echo studies reveal a hyperkinetic LV with increased fractional shortening.

C

Management

• 1.

  In severely affected patients, a β-adrenergic blocker such as propranolol is indicated to reduce the effect of catecholamines.

• 2.

  Treatment of hyperthyroidism consist of oral administration of antithyroid drugs, propylthiouracil or methimazole (Tapazole).

• 3.

  If CHF develops, treatment with anticongestive medications is indicated.

A

Description

• 1.

  Congenital type. Clinical signs may not appear until 3 months of age. A protuberant tongue, cool and mottled skin, subnormal temperature, carotenemia, and myxedema are typical. Untreated children become mentally retarded and slow in physical development.

• 2.

  Acquired type. It may be caused by lymphocytic thyroiditis (Hashimoto disease or autoimmune thyroiditis), subtotal or complete thyroidectomy, or protracted ingestion of goitrogens, iodides, or cobalt medications. Rarely, amiodarone can cause hypothyroidism. Serum T ₃ and T ₄ are low or borderline and TSH is high. Hypercholesterolemia is common.

B

Cardiovascular Manifestations

• 1.

  Significant bradycardia, weak arterial pulse, hypotension, and nonpitting facial and peripheral edema may be present.

• 2.

  The ECG abnormalities may include some or all of the following: low QRS voltages, especially in the limb leads; low T-wave amplitude; prolongation of PR and QT intervals; and dome-shaped T wave with an absent ST segment (“mosque” sign).

• 3.

  Echo studies may show pericardial effusion, hypertrophic cardiomyopathy, or asymmetric septal hypertrophy.

• 4.

  In congenital type, PDA and PS are frequently found.

• 5.

  There is an increased occurrence of hypercholesterolemia in acquired type.

C

Management

• 1.

  L-thyroxine given orally is the treatment of choice. Monitor T ₄ and TSH frequently.

• 2.

  In acquired type, treatment of hypercholesterolemia, if present.

A

Description

• 1.

  In general, infants of diabetic mothers (IDM) have higher prevalence of congenital malformations of multiple organ systems, occurring at three to four times the rate seen in the general population. Common ones include neural tube defects (anencephaly, myelomeningocele), CHDs (such as ASD, VSD, TGA, tricuspid atresia, COA, etc.), and sacral dysgenesis or agenesis.

• 2.

  In addition to the high prevalence of congenital anomalies, IDMs have a high prevalence of cardiomyopathy and persistent pulmonary hypertension of newborn (PPHN).

  • a.

    Hypertrophic cardiomyopathy (either concentric or asymmetric septal hypertrophy) with or without obstruction is seen in 10% to 20% of the patients.

  • b.

    An increased risk of PPHN may be due to conditions that promote the persistence of pulmonary hypertension, such as hypoglycemia, perinatal asphyxia, respiratory distress, and polycythemia.

B