hypotension in tachycardia

[mrmeaner]

Sadly, knowing the answer to this question will help me sleep at night. Is hypotension in tachycardia (190 bpm) caused by shortened systolic or diastolic time. I can see arguments for both both sides. Any help would be greatly appreciated.

[rayemtjax77]

That particular situation, the shortened time would be Diastolic. Due to the fact that the heart is not pumping as efficent as it needs to be... there for teh pressure going out of the heart will be the lesser of the 2.

Sadly, knowing the answer to this question will help me sleep at night. Is hypotension in tachycardia (190 bpm) caused by shortened systolic or diastolic time. I can see arguments for both both sides. Any help would be greatly appreciated.

[AZCEP]

The heart is dependent on preload to generate the myocardial stretch for an effective contraction. The preload is created by the diastolic filling of the right and left ventricles. The systolic contraction remains fairly constant up to rates greater than 250 beats per minute.

Your answer is diastolic, not systolic.

[Ridryder 911]

Ditto.... poor ventricular filling time.

R/r 911

[Rezq304]

The heart is dependent on preload to generate the myocardial stretch for an effective contraction. The preload is created by the diastolic filling of the right and left ventricles. The systolic contraction remains fairly constant up to rates greater than 250 beats per minute.

Your answer is diastolic, not systolic.

Exactly!

[Dustdevil]

If systolic time were decreasing, you would see a shortening of the QRS. Compare the EKG of a person before or after the tachycardic event to the one during the tachycardia and you will see the QRS does not change (unless there is pathology behind the event). It's the same QRS just being repeated more rapidly. Therefore, it is only the interval between systoles that changing. The interval between systoles is diastole.