hypoparathyroidism cardiomyopathy
Introduction
Introduction to hypoparathyroidism Chronic hypothyroidism that is not detected and treated in time may involve the cardiovascular system due to long-term hypocalcemia and hypomagnesemia, manifested as decreased myocardial tension, dilatation of the heart chamber, arrhythmia, and congestive heart failure, called parathyroidism. Hypoparathyroid cardiomyopathy. basic knowledge The proportion of illness: 0.002% Susceptible people: no special people Mode of infection: non-infectious Complications: Epilepsy Arrhythmias Heart Failure
Cause
Causes of hypoparathyroidism
(1) Causes of the disease
1. Postoperative parathyroid gland hypofunction in all hypothyroidism, parathyroidism after surgery is the most common, parathyroid hyperplasia in the parathyroid gland, or again for parathyroid surgery are easier Parathyroidism after surgery.
2. Idiopathic hypoparathyroidism is a rare disease, mostly sporadic, about one-third of patients with parathyroid antibodies in the blood, indicating that the cause of this disease is related to autoimmunity.
(two) pathogenesis
PTH has a positive inotropic effect on the myocardium. PTH reduction or deficiency can directly reduce myocardial contractility, and more importantly, cause hypocalcemia, low blood magnesium, affecting the excitatory-contraction coupling process of myocardial fibers, PTH and digitalis. Positive inotropic effects are also often dependent on the concentration of calcium in the extracellular fluid, long-term hypocalcemia, can seriously affect myocardial contractile function, Conor believes that when serum calcium drops to 1.8mmol / L, it can lead to congestive heart failure, low Blood calcium also affects the electrophysiological properties of cardiomyocytes and induces arrhythmia. In addition, calcium also affects the reabsorption of sodium by the renal tubules. Sodium excretion is reduced when hypocalcemia is present. Sodium water retention can aggravate cardiac load. Patients with chronic hypoparathyroidism The blood magnesium also has different degrees of decline. Because magnesium ions are the activators of ATP to cAMP, low magnesium can cause cAMP to decrease, leading to myocardial damage and impaired cardiac function.
Prevention
Parathyroid hypofunction cardiomyopathy prevention
1. Guardianship of patients with potentially dangerous factors (such as those who have done previous anterior neck surgery, those with multiple endocrine gland failure, cataracts, unexplained convulsions, numbness of the extremities, tingling, hemifacial spasm, etc. ) Regular blood calcium testing should be done once a year to monitor the development of the disease.
2. To prevent the occurrence of hypoparathyroidism in early prevention of cardiomyopathy, the correction of blood calcium reduction at the parathyroid is essential for the treatment of this disease. In the early stage of the disease, the heart changes can be gradually restored after the recovery of blood calcium.
Complication
Parathyroid hypofunction cardiomyopathy complications Complications epilepsy arrhythmia heart failure
The disease is prone to psychotic manifestations, epileptic seizures, chronic hand and foot convulsions, poor eyesight, heart failure, arrhythmia and other complications.
Symptom
Symptoms of hypoparathyroidism Cardiomyopathy Common symptoms Tachycardia Parathyroid gland hypofunction Anxiety Pericardial effusion Skin rough irritability Restless limb numbness QT interval Prolongs hair loss
Neuromuscular manifestation
Long-term hypocalcemia can cause limb paresthesia, tingling, numbness and facial muscle spasm of the hands and feet. The typical manifestations are hand, foot and ankle, which may be positive for Babinski's sign, caused by calcification of the basal ganglia, and anxiety may occur in some cases. Mental symptoms such as irritability, hallucinations, and physical examination were positive for the facial paralysis test (Chevostek sign) and the beam arm compression test (Troussean sign).
2. Ectodermal tissue vegetative degeneration
It is characterized by rough skin, pigmentation or hair loss. 50% of cases have cataracts, often bilateral, and the age of onset is early.
3. Cardiovascular system performance
After the activity, palpitations, shortness of breath, limb edema, and finally can lead to congestive heart failure, and have the corresponding symptoms, signs, literature reports, the shortest course of parathyroidism before congestive heart failure is 8 years and 7 months, the most Up to 40 years, see the prolongation of QT interval in ECG, mainly ST segment extension, T wave low or inverted, tachycardia, hypocalcemia often makes the heart sensitive to the action of catecholamines, can occur atrial or room Arrhythmia, even sudden death, echocardiography can be seen in the atria, ventricular cavity enlargement, ventricular septal ventricular systolic thickening, pulsatile amplitude, similar to dilated cardiomyopathy, may have pericardial effusion.
Examine
Examination of hypoparathyroidism
1. Blood calcium is reduced, mostly lower than 2.0mmol/L, blood phosphorus is increased, and more than 1.6mmol/L.
2. Serum immunoreactive parathyroid hormone (iPTH) was significantly reduced or not detectable.
3. Serum alkaline phosphatase is normal.
4. Electrocardiogram: ECG sees QT interval prolongation, mainly ST segment extension, T wave low or inverted, tachycardia.
5. Echocardiography: visible atrial, ventricular cavity enlargement, ventricular septal ventricular systolic thickening, pulsation amplitude decreased, similar to dilated cardiomyopathy, may have pericardial effusion.
6. Chest X-ray: The heart is enlarged to both sides, and the lung texture is increased and thickened, showing pulmonary congestion and pulmonary edema.
Diagnosis
Diagnosis and differentiation of hypoparathyroidism
Diagnostic criteria
There are repeated episodes of hand and foot convulsions, Chevostek and Troussean signs positive, laboratory tests see blood calcium reduction, elevated blood phosphorus, serum PTH significantly reduced or can not be measured, can diagnose primary hypoparathyroidism, combined with clinical involvement of the heart , ECG and echocardiographic evidence to diagnose hypoparathyroidism.
Differential diagnosis
The disease should be differentiated from diseases that cause hypocalcemia, such as insufficient supply of vitamin D or poor absorption, renal failure, osteoblastoma, acute pancreatitis, thyroid myeloma and other diseases.
Renal insufficiency
According to the history of chronic kidney disease, urine samples routinely detect protein, red blood cells and casts; blood urea nitrogen, elevated creatinine can help to establish a diagnosis, in case of low blood calcium, high blood phosphorus patients, PTH measured more, and hypothalamic PTH decreased Can be identified.
2. Dilated cardiomyopathy
The heart of the disease is enlarged, heart failure is easy to occur, and it needs to be differentiated from hypothyroidism. The latter has hypothyroidism, special neuromuscular and ectodermal tissue dystrophic and abnormal calcification syndrome, and the laboratory receives hypocalcemia and high. Blood phosphorus, and PTH decreased, heart failure can be significantly improved after effective calcium supplementation.
