A Diagnosis From The Heart
Bradley A. Radwaner, M.D., F.A.C.C.
In the ambulance on the way to the hospital, a diagnosis of coronary heart disease can be ominously exact. Almost half of Americans suffering a heart attack die before they reach the hospital; another 15 percent do not survive hospitalization.
While a heart attack is an emergency that often gives little or no warning, the disease that causes it is progressive, often starting during the teen years. Over the past two decades the heart attack death rate has been nearly halved for men and significantly reduced for women, thanks not just to improved therapies and more sophisticated technology at the hospital but also to earlier and better diagnosis. We also now know that the majority of heart attacks occur from cholesterol deposits that suddenly rupture into the bloodstream, causing clots that obstruct the blood flow completely.
THE HISTORY AND PHYSICAL
Your family physician can get a fairly good idea of your cardiovascular health through a history and physical. Many things can go wrong with the heart, but the most common cause of a heart attack is insufficient blood flow due to narrowing or blockage of one or more coronary arteries.
Without adequate blood flow, the body cries for oxygen, often through pain in the chest area or shortness of breath that comes with exertion but goes away with rest.
Other signs of a problem include coughing up blood or blood-streaked sputum: palpitations; swelling; faintness or dizziness, and bluish discoloration (cyanosis) of the skin or mucus membranes.
If you’re having shortness of breath or chest pain, your physician can learn a lot by talking to you about when your symptoms appear and exactly where and how you feel discomfort.
The physician may also note signs of physical appearance, including clubbing or other changes in the fingers or thumbs, an abnormal gait, a head bob or exaggerated pulsations of arteries in the neck. The physician can measure venous and arterial pressure and pulse, feel for abnormalities in the chest, listen to the heart through a stethoscope and perhaps order tests, including chest X-rays and an electrocardiogram (EKG).
Chest X-rays can rule out non-cardiovascular causes of the symptoms as well as provide information about the size of heart chambers and major blood vessels. The most widely used non-invasive diagnostic procedure, the EKG depicts the electrical activity produced by the heart. Certain abnormalities in the rhythm, pumping action or blood flow can be detected even at rest.
New advanced lipid analysis not only identifies LDL (bad) and HDL (good) cholesterol levels, but also looks at particle size. We now know that those patients who make a predominance of small LDL particles have a 300% greater risk of developing coronary blockages than those who predominantly make large LDL particles. Large HDL particles are involves in reverse cholesterol transport, moving cholesterol away from the heart and storing it safely in the liver. With exercise and certain medications, the particle size can be dramatically improved.
To get an idea of how your heart performs in action, the physician may ask you to wear a Holter Monitor, a portable EKG device that is carried throughout the day, or undergo a full scale exercise stress test on a treadmill.
Performed under the supervision of a physician, the treadmill stress test proceeds slowly and gradually through several levels. It is designed not to push you to your limits but to determine exactly what level of exercise your heart can safely withstand.
If necessary, additional tests such as a thallium scan (injection of a radioactive dye into your blood that can be traced during an exercise EKG to indicate trouble spots) can pinpoint the location and cause of the problem.
Other specialized tests include:
- Echocardiography: using sound waves to evaluate the structure and motion of the heart.
- Radionuclide imaging: computer-generated pictures that track radionuclides in the blood stream in order to determine how well the heart muscle is supplied with blood and how the chambers are functioning.
- Magnetic Resonance Imaging (MRI): these detailed images can detect damage from a previous heart attack, identify congenital defects and evaluate blockage of larger blood vessels.
- Calcium is a marker for atherosclerosis development. If someone has calcium deposits already present, this is an indication that the process of cholesterol building in the arteries has begun. Recent studies have shown that a high calcium score indicates a high risk of a heart attack in the next 4 years and is a predictor independent of your cholesterol level.
- CT angiography also uses ultrafast, CAT scans to get noninvasive 3D images of the coronary arteries that before could only be obtained by cardiac catheterization. This noninvasive test will likely replace 75% of diagnostic cardiac cath over the next 10 years. Ultrafast CAT scans providing a reading of the amount of calcium in the coronary arteries.
The definitive approach has been cardiac catheterization, usually prescribed to determine if surgery or balloon angioplasty is necessary. Typically on an outpatient basis, a flexible tube (catheter) is inserted into a blood vessel in the arm and then threaded through the body to reach the openings of the major arteries near the heart. In terms of discomfort, one patient compared it to “getting a tooth drilled under novocaine.”
The films, produced within a matter of hours, give a detailed picture of the location and extent of obstructions, providing an excellent guide for future procedures.
A narrowing in your left main coronary artery (which is the major supplier of blood to the heart) or in three other primary arteries usually indicates bypass surgery. If obstruction is less extensive, angioplasty or other procedures may offer just as much chance of prolonging life.
While the technology is available to diagnose and treat even the most advanced cases of coronary artery disease, the most highly trained and advanced cardiologists, i.e., Dr. Radwaner, prefer to prevent coronary artery heart disease before it is present and reverse the disease when it has already taken hold.