The causes of sudden heartburn and heart block are as follows: 1, most likely paroxysmal supraventricular tachycardia attack, this disease is characterized by sudden and sudden, without any signs, can be clarified by doing electrocardiography, if it is supraventricular tachycardia, you can use drugs to control it first, such as metoprolol, etc., and if the drug control is not good, radiofrequency ablation can be considered as a treatment; 2, sudden angina pectoris or Myocardial infarction, especially the lower wall of myocardial ischemia, can also appear suddenly hard to heart, heart congestion symptoms, can be clarified by electrocardiogram, laboratory cardiac enzymes and other tests; 3, sudden gastroesophageal reflux leading to esophageal spasm, can also appear in the above symptoms.