1.0Glossaryhttps://www.healthbenefitstimes.com/glossaryGlossaryhttps://www.healthbenefitstimes.com/glossary/author/adminglossary/rich600338<blockquote class="wp-embedded-content" data-secret="WQLYIdt6RV"><a href="https://www.healthbenefitstimes.com/glossary/congenital-heart-block/">Congenital heart block</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.healthbenefitstimes.com/glossary/congenital-heart-block/embed/#?secret=WQLYIdt6RV" width="600" height="338" title="“Congenital heart block” — Glossary" data-secret="WQLYIdt6RV" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://www.healthbenefitstimes.com/glossary/wp-includes/js/wp-embed.min.js </script> Congenital heart block occurs when there is an interference with the normal conduction of electrical impulses that control the heart muscle, particularly between the upper and lower heart chambers. Varying degrees of this condition exist: In first-degree heart block, the contractions of the lower chambers (ventricles) lag slightly behind the two upper chambers of the heart (atria). In second-degree heart block, one half of the atrial beats are conducted to the ventricles. In complete heart block (third degree), the ventricles and the atria beat independently.Heart block present at birth, caused by faulty cardiac development in the womb, autoimmune diseases, or other causes.