Cardiac tamponade: compression of heart via fluid accum. In pericardial cavity Ventricles can’t fill properly
The fossa ovalis is a prominent depression in the interatrial septum. This is where there was an opening in the septum of the fetal heart. This allowed blood to by-pass circulation through the non-functioning fetal lungs and be circulated through the umbilical cord to the placenta instead.
MVP can cause chest paint, fatigue and shortness of breath. Often, however, it is not dangerous. Much more common in women, particularly those between 20 and about 40. Link is to an animation of stenosis.
Cor pulmonale: right ventricular failure due to high afterload in the pulmonary circuit (emphysema, chronic bronchitis, black lung disease).
Nine risk factors for CAD: heredity, age, gender (these three you can’t change!); obesity, diabetes, smoking, inactivity, hypertension (also, some researchers argue high cholesterol), stress.
“ Fig. 1. Figure 1. Initial arteriogram shows lefi common iliac artery (CIA) occlusion (arrows) and stenosis of left extrenal iliac artery (EIA) (arrow). Fig. 2. Appearance after placement of Palamz stent in the CIA and angioplasty of the EIA.” From: http://www.scvir.org/members/caseclub/1298/1298_04/1298_04.htm, 7/30/04.
NE and E act through cAMP to open Ca2+ gates. This increases contractility and thus has a positive inotropic effect. Glucagon stimulates cAMP formation and is sometimes used for emergency heart attack treatment in combination with calcium chloride. Digitalis treat congestive heart failure by inhibiting Na/K pumps, thus raising intracellular Na concentration and increasing Ca in sarcoplasm. Hypercalcemia causes excess Ca flow into sarcoplasm = strong, prolonged contraction. Hyperkalemia has a negative inotropic effect by decreasing the myoaction potentials and reduing Ca in sarcoplasm. Afterload is like adding more weight (hypertension) behind a door (aortic valve) that’s being slammed by a battering ram (blood in the left ventricle).
Acetylcholine opens K channels to cause hyperpolarization, and fewer heart beats. Foxglove (digitalis): positive inotropic and negative chronotropic
The Heart: Did you know?
the size of your heart is equal to that of your fist
the human heart creates enough pressure in the left ventricle to squirt blood 9.1 metres
According to German researchers, the risk of heart attack is higher on Monday than any other day of the week.
human heart rate = 100,800 beats/day
fetal heart starts beating during fourth week of pregnancy