Central  South  Dakota  Medical News
The Clinical View
  by P.E. Hoffsten, M.D.
19, November 2003

WHAT IS DIASTOLIC HEART FAILURE?

    The patient was a rancher-cowboy.  He was 63 years old taking no medications and feeling fine.  A friend had recently been found to have carcinoma of the prostate so this cowboy came in to get checked out and be sure that he didn’t have something wrong.  He indicated that he rode a horse every day, checking fences and his cattle, being sure that everything was o.k.  He never got chest pain.  He was sleeping well.  His breathing was normal.  He thought everything was o.k. but he just wanted to be sure.

     As part of his checkup an electrocardiogram was done which showed slight abnormalities.  An exercise stress test was done and this showed that his heart was o.k. as a pump.  But his blood pressure went very high during the exercise portion of the test.  To have your blood pressure go up when you are exercising is rather like going down the road in your car but with the brakes on.  Everything wears out a little sooner.

     We did a special kind of test called an echocardiogram which takes a picture of the heart with sound waves.  This gives a clear picture of the heart in three dimensions.  It showed this cowboy’s heart was very thick.  A thick heart muscle comes from the heart having to beat against a high blood pressure.  Just like a normal muscle in your arm gets stronger when you exercise it and lift weights, your heart gets thicker when it has to push against a high blood pressure.  High blood pressure is the heart’s answer to lifting weights.  Lifting weights may be good for your arms but it is not good for your heart.

     This gentleman has “diastolic heart failure”.  He asked to see his medical record and copies of his tests and saw that word written down on his clinic notes.  He wanted to know what diastolic heart failure was.

     To begin the explanation, I pointed out to him that a normal heart beats about 72 times a minute, a little faster than once every second.  Each heartbeat empties about 2/3’s of the blood out of the heart.  At rest, the heart pumps about 5 quarts of blood a minute.  If the heart muscle gets too weak it can’t empty out completely and more blood than normal is left behind between each heart beat.  This is called “systolic heart failure” and it results from factors that weaken the heart muscle.

     Diastolic heart failure is almost like the mirror image of systolic heart failure.  A person with diastolic heart failure has a heart muscle that is too thick and too stiff for the heart to fill up easily.  A normal healthy heart is strong with each heartbeat but is floppy when it relaxes so it can fill up with blood easily for the next heartbeat.  If the heart muscle is stiff and doesn’t relax easily, then the pressure to fill to it up for the next heartbeat comes from the lungs.  When the blood pressure in the lungs goes up to fill a stiff heart, then the lungs have more blood in them than normal which means there is not as much air in there as you want either.  Without as much air as you want, you become fatigued and short of breath with exertion.  Thus, the measure of diastolic heart failure is what might be called “deconditioning”.  A person with diastolic heart failure looses their athletic capability and their ability to do the hard work that cowboys and other people do.  The worst part of diastolic heart failure is that it predisposes the person to a host of major medical problems such as heart attacks and eventually a weakening of the heart’s contraction ability with the development of systolic heart failure or sudden death.  Systolic heart failure is a very severe disabling condition.

    Thus simply put, diastolic heart failure is the result of too much blood pressure on a normal heart for too long so that the heart gets thicker and stiffer than normal.  This requires an increased pressure to fill it up.  That pressure comes from the lungs and thus the first symptom that the person develops is shortness of breath from deconditioning.  Most people attribute this to “just getting old”.  The truth is that keeping the blood pressure down and maintaining some element of physical conditioning is critical to a person’s long term well being and health.

    The cowboy that we talked about above was advised of all of this.  He said that he hated to take pills.  He just couldn’t image himself doing that.  I asked if he could imagine himself sitting in a chair so short of breath that he couldn’t ride a horse anymore and he said that he really didn’t want to do that either.  I suggested that taking a pill was a whole lot easier.  He was started on a medication that will help lower his blood pressure, help decrease the thickness of his heart muscle and prevent future strokes and heart attacks.  These changes take a year to two years to reverse problems that have developed for forty years but the problem can be reversed.

     The moral of the story is some medical problems such as diastolic heart failure occur slowly and are found suddenly.  If you can reverse the problem at an early time, those sudden ugly surprises such as strokes, heart attacks and heart failure can be prevented.