The best example of S1 variation with P-R interval occurs in complete heart block, in which atrial and ventricular contractions are dissociated.是什么意思_The best example of S1 variation with P-R interval occurs in complete heart block, in which atrial and ventricular contractions are dissociated.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句