Left bundle branch blockLeft bundle branch block (LBBB) is a conduction abnormality in the heart that can be seen on an electrocardiogram (ECG). In this condition, activation of the left ventricle of the heart is delayed, which causes the left ventricle to contract later than the right ventricle. Among the causes of LBBB are: Aortic stenosis Dilated cardiomyopathy Acute myocardial infarction Extensive coronary artery disease Primary disease of the cardiac electrical conduction system Long standing hypertension leading to aortic root dilatation and subsequent aortic regurgitation Lyme disease Slow or absent conduction through the left bundle branch means that it takes longer than normal for the left ventricle to fully depolarise.
Interventricular septumThe interventricular septum (IVS, or ventricular septum, or during development septum inferius) is the stout wall separating the ventricles, the lower chambers of the heart, from one another. The ventricular septum is directed obliquely backward to the right and curved with the convexity toward the right ventricle; its margins correspond with the anterior and posterior interventricular sulci. The lower part of the septum, which is the major part, is thick and muscular, and its much smaller upper part is thin and membraneous.
Nitroglycerin (medication)Nitroglycerin, also known as glyceryl trinitrate (GTN), is a vasodilator used for heart failure, high blood pressure, anal fissures, painful periods, and to treat and prevent chest pain caused by decreased blood flow to the heart (angina) or due to the recreational use of cocaine. This includes chest pain from a heart attack. It is taken by mouth, under the tongue, applied to the skin, or by injection into a vein. Common side effects include headache and low blood pressure. The low blood pressure can be severe.
Third heart soundThe third heart sound or S3 is a rare extra heart sound that occurs soon after the normal two "lub-dub" heart sounds (S1 and S2). S3 is associated with heart failure. It occurs at the beginning of the middle third of diastole, approximately 0.12 to 0.18 seconds after S2. This produces a rhythm classically compared to the cadence of the word "Kentucky" with the final syllable ("-CKY") representing S3. One may also use the phrase "Slosh’-ing-IN" to help with the cadence (Slosh S1, -ing S2, -in S3), as well as the pathology of the S3 sound, or any other number of local variants.
Atrial tachycardiaAtrial tachycardia is a type of heart rhythm problem in which the heart's electrical impulse comes from an ectopic pacemaker (that is, an abnormally located cardiac pacemaker) in the upper chambers (atria) of the heart, rather than from the sinoatrial node, the normal origin of the heart's electrical activity. As with any other form of tachycardia (rapid heart beat), the underlying mechanism can be either the rapid discharge of an abnormal focus, the presence of a ring of cardiac tissue that gives rise to a circle movement (reentry), or a triggered rapid rhythm due to other pathological circumstances (as would be the case with some drug toxicities, such as digoxin toxicity).
Venae cavaeIn anatomy, the venae cavae (ˈviːni_ˈkeɪvi; : vena cava ˈviːnə_ˈkeɪvə; ) are two large veins (great vessels) that return deoxygenated blood from the body into the heart. In humans they are the superior vena cava and the inferior vena cava, and both empty into the right atrium. They are located slightly off-center, toward the right side of the body. The right atrium receives deoxygenated blood through coronary sinus and two large veins called venae cavae.
