the sinoatrial node (present in the right atrium) starts the cardiac cycle by producing an action potential which is then transmitted rapidly to the left atrium (causing contraction of both atria) & the ventricles during which are relaxed (diastole) then through the atrioventricular node, the impulses are then transmitted from the atria to the ventricles & then through the bundle of Hiss then left & right bundle branches to all of the ventrricular muscle causing contraction of both ventricles & thus systole
Any defect in the conductive system like ectopic foci (focus producing action potential other than the SA node) or AV block (no impulse transmission from atria to ventricles) leads to defective filling of the heart & pumping of blood
Ischemia occurs when there is not enough oxygenated blood reaching the cardiac muscle cells.
Cardiac output will level off as your heart muscle strengthens and your body becomes accustomed to physical activity. For example, when first getting started, walking 5 minutes may be enough to increase your heart rate, but within a few weeks, you will need to increase the intensity of your walk to increase your heart rate by the same amount.
The heart does not have enough time between contractions to fill with enough blood to maintain adequate cardiac output. This is especially a concern because the heart itself is perfused during diastole (the period between ventricular contractions).
There is no evidence that cellphones can directly contribute to heart attacks, (unless there is extremely bad news on the other end of the line). To provoke a heart attack, the phone would need to exert enough energy to dislodge a coronary artery plaque, or create a clot to block an artery. The amount of radiant energy produced during a cell phone call is not enough to cross the chest wall, much less have an impact on the cardiac tissues. Persons with pacemakers however, are cautioned to avoid placing any electronic device that might produce a magnetic field, near their pacemaker. Magnets are used to program and control both pacemakers and Automatic Internal Cardiac Defibrillators (AICDs), and there have been reported interference in function of these devices from the magnets from ear-bud speakers and cell phones, when placed in direct proximity of the device.
Myocardial infarction (MI) can lead to heart failure in numerous ways. First of all, early on, the heart muscle does not contract well because it is not receiving enough oxygen and other necessary substrates, so stroke volume is decreased, which may lead to congestive heart failure. Later on, if the MI is aborted with thrombolytics or with a cardiac catheterization and thrombectomy, the myocardium may be stunned, or hibernating, because of the lack of oxygen, and may return to normal function over time. If the MI completes, the portion of cardiac muscle that was affected is dead. Depending on how significant a portion that is, losing the muscle alone may result in heart failure. The dead portion of the heart will later turn into a scar, which is noncontractile and also does not allow for the normal stretch, so it may affect preload and contractility in that way as well, decreasing cardiac output and possibly leading to congestive heart failure.
It require the medium with conduction property. The medium must be stable enough to withstand heat and not thermally decompose. It is then apply temperature difference to start such conduction heat transfer.
Enough to get rich in short order.
No it can't because the particles are not close enough for the heat to be transferred
The answer is conduction
Cardiac (pertaing to the heart) failure (no function). The heart stops working and the tissues do not recieve enough oxygen in the blood and a person will die in a few minutes.
There are not enough of them. Their distribution acording to needs and resources is uneven and injust.
Cardiac means "of or relating to the heart". Cardiac muscle has that name because it is the specific kind of muscle found only in the heart. It is a very special kind of muscle, very efficient and different from other muscles.
If the wall thins enough, the patient goes into cardiac failure.
Ischemia occurs when there is not enough oxygenated blood reaching the cardiac muscle cells.
Yes, ischemia leads to heart arrest.
The myocard (cardiac muscle), the muscle that makes your heart pump, needs oxygen to function. This oxygen is distributed through the blood that flows in the coronary arteries, which lie around the cardiac muscle. When there is not enough oxygen in your blood, the cardiac muscle does not get enough oxygen to fully function and your heart will not be able to function, over time. This starts at about 3 minutes after stopping to get oxygen.
To your heart, if the bubble is large enough it means cardiac arrest