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The Cardiac System

The Cardiac System

Purpose: The cardiac system serves as the pump, propelling oxygenated blood to our vital organs and accepting it in return for another cycle through our circulation. Analogous to the engine in our automobiles, it is sophisticated and occasionally prone to breakdown.
 
The Heart Muscle: The muscle or myocardium is divided into four cardiac chambers, each specialized and functioning separately though in sequence. The most vital is the left ventricle, responsible for the final thrust of blood into our vessels, and prone to damage through heart attack or myocardial infarction.
 
The Coronary Arteries: Coursing on the surface of the heart muscle, the three named coronary arteries serve to provide the myocardium with oxygen and nutrition. Ranging from 3-4 millimeter arteries to tiny capillaries, the coronary arteries are remarkably prone to developing atherosclerotic obstructions, frequently related to our diet and lifestyle habits. It is Vessel Health's premise that the health of the coronary arteries serves as the foundation of cardiac health. 
 
Heart Valves: The aortic, mitral, tricuspid and pulmonic valve are each interposed between the four cardiac chambers. Delicate and constantly flexing, they serve as “check valves” impeding the reverse flow of blood through the heart.  Although the history of medicine records the problems accrued to these valves by rheumatic fever, they are now more commonly affected by the complications of heart attack and congestive heart failure, or weakening of the heart muscle.
 
Electrical System: Like our cars, the cardiac system is electrically “wired,” with circuits of specialized heart tissue embedded in the myocardium. Responsible for the timing of our heart beat and the coordinated contraction of our heart chambers, the electrical system is both prone to its own independent problems as well as several that are the result of damage to the circulation, namely the coronary arteries and heart muscle.
 
Potential Problems

Coronary Atherosclerosis: Coronary Atherosclerosis, or “hardening of the heart arteries” is the paramount health issue confronting developed civilizations today. A complex phenomenon, atherosclerosis involves the abnormal function of the lining of the heart arteries with resultant inflammation, development of porosity, and deposition of a heterogeneous matrix of cholesterol, blood clotting platelets, and a wide array of inflammatory substances. Unless stopped or reversed, this self-amplifying process eventually results in deposition of calcium, creating an encrusted plaque, hence the term “hardening.”
 
Myocardial Infarction: As coronary plaque builds and matures, it goes through a phase of fragility during which it is prone to rupture and exposure of its contents to the surrounding blood stream.  Recognizing the foreign nature of plaque contents, the blood reacts by forming a “clot” in the region of the disrupted plaque. In the most acute of settings, this clot totally obstructs the coronary artery to blood flow, yielding a heart attack or myocardial infarction. Like a frostbitten limb, the heart muscle supplied by the coronary artery undergoes a process of cell death.  Different than the frozen extremity, the demise of the heart muscle is rapid and of grave consequence. Unless measures such as thrombolysis (blood clot dissolution) or angioplasty (mechanical opening) are immediately undertaken, the heart muscle may suffer irreparable consequence within 6 hours. Hence the term “time is muscle” in heart attack care.
 
Heart Failure: Congestive heart failure is the symptom complex of fluid retention that accrues from a distinct deterioration of cardiac function.  Commonly, the left ventricle ejects over half of its cavity contents with each heart beat. Characteristically, the “ejection fraction” is therefore in the range of 55-65%. Cardiac damage resulting from myocardial infarction or viral illnesses can often impair cardiac performance yielding ejection fractions below 35%. The body responds with a number of counterproductive responses mediated by several hormonal mechanisms which result in fluid retention amongst other manifestations. Although the medical community has identified a number of therapeutic medications as well as the use of sophisticated pacemakers in certain conditions, the outlook for many patients may be poor. Therefore, maximizing vascular health and preventing damaging cardiac conditions remains a pivotal goal.
 
Valve Dysfunction: Given a gradual reduction in the prevalence of rheumatic heart disease resulting from childhood illness, the remaining valve conditions seen by cardiologists are generally related to myocardial dysfunction, or aging. Regurgitation of blood through an incompetent mitral valve may be the most common of such disorders. In extreme conditions surgical valve replacement may be indicated although medical management is of first priority. As with other cardiac complications, every effort to avert their presence is optimal.
 
Arrhythmias:  As with valve disease, certain cardiac arrhythmias may be the direct consequence of coronary atherosclerosis and myocardial infarction. In particular, certain forms of “heart block” may be created and require pacemaker implantation. Moreover, a highly damaged heart muscle can also lead to life threatening rapid heartbeat (tachycardia).  Under certain circumstances an implantable defibrillator has proven life saving. These conditions are often treated by a cardiology subspecialist know as an electrophysiologist.



The cardiac system consists of:

  • The Heart Muscle
  • Coronary Arteries
  • Heart Valves
  • Electrical System

Potential problems include:

  • Coronary Atherosclerosis
  • Myocardial Infarction
  • Heart Failure
  • Valve Dysfunction