Developer site: The content shown here is test data.

MyEClinic
MyEClinic
Health Dictionary AI Health Chat Find an Online Doctor
A serene Zen garden with raked sand and smooth stones, symbolising clarity and calm

Health Dictionary

Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.

Back to skin conditions

Deceleration

Introduction

Synonyms and keywords: deceleration of diastolic flow; deceleration time of diastolic flow velocity (DDT)

Overview

Overview

The deceleration time of diastolic flow may be a parameter to evaluate the degree of microvasculature damage that might predict the residual myocardial viability assessed by angiography.

Definition

Definition

  • Deceleration is defined as when dye flow down in the artery is slowed at any point during the course of flow.
  • The diastolic deceleration rate (m/s2) refers to the calculation of the rate of decline in flow velocity in diastole.[1]
Pathophysiology

Pathophysiology

Microvascular ischemic damage after epicardial coronary artery occlusion affects coronary vascular resistance and may result in perivascular edema in which the generation of capillary leukocyte plugging contributes to prevention of full restoration of myocardial perfusion.[2][3][4] Thus, the deceleration time of diastolic flow velocity may be explained as an increase in coronary vascular resistance caused by such ischemic microvascular impedance which significantly affects total coronary resistance in patients without severe coronary stenosis.[2][3][4][5][6] Hence, this fact explains the reduction in postprocedural coronary systolic flow velocity in patients with no-reflow and is also the reason for a significantly increase in total coronary resistance in patients without severe coronary stenosis.[1][7]

The deceleration time of diastolic flow velocity might reflect the coronary blood flow and is represented by a high ratio of perfused myocardium per functioning coronary microvasculature. So, the degree of reduced systolic antegrade flow or the deceleration time of diastolic flow evidence the level of microvasculature damage and be predictive of residual myocardial viability. Thus, the coronary blood flow velocity pattern seems almost normal in viable myocardium but is reduced in nonviable myocardium due to a systolic retrograde flow and a rapid deceleration of diastolic flow velocity.[5]

Clinical Significance

Clinical Significance

The coronary blood flow velocity pattern of no-reflow in patients with reperfused AMI is characterized by the occurrence of:

  • Systolic retrograde flow.[1]
  • Diminished systolic antegrade flow.[1]
  • Rapid deceleration of diastolic flow.[1]
  • May occur immediately after reperfusion or shortly thereafter.[8]

Disturbances are present during the deceleration phase of systole related to mild to moderate stenosis.[9]

Example

Example

Deceleration (Left Anterior Descending Artery)
Deceleration (Left Anterior Descending Artery)
References

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 Iwakura, K.; Ito, H.; Takiuchi, S.; Taniyama, Y.; Nakatsuchi, Y.; Negoro, S.; Higashino, Y.; Okamura, A.; Masuyama, T. (1996). “Alternation in the coronary blood flow velocity pattern in patients with no reflow and reperfused acute myocardial infarction”. Circulation. 94 (6): 1269–75. PMID 8822979. Unknown parameter |month= ignored (help)
  2. ↑ 2.0 2.1 Frame, LH.; Powell, WJ. (1976). “Progressive perfusion impairment during prolonged low flow myocardial ischemia in dogs”. Circ Res. 39 (2): 269–76. PMID 939013. Unknown parameter |month= ignored (help)
  3. ↑ 3.0 3.1 Gorman, MW.; Sparks, HV. (1982). “Progressive coronary vasoconstriction during relative ischemia in canine myocardium”. Circ Res. 51 (4): 411–20. PMID 7127678. Unknown parameter |month= ignored (help)
  4. ↑ 4.0 4.1 Engler, RL.; Schmid-Schönbein, GW.; Pavelec, RS. (1983). “Leukocyte capillary plugging in myocardial ischemia and reperfusion in the dog”. Am J Pathol. 111 (1): 98–111. PMID 6837725. Unknown parameter |month= ignored (help)
  5. ↑ 5.0 5.1 Kawamoto, T.; Yoshida, K.; Akasaka, T.; Hozumi, T.; Takagi, T.; Kaji, S.; Ueda, Y. (1999). “Can coronary blood flow velocity pattern after primary percutaneous transluminal coronary angioplasty [correction of angiography] predict recovery of regional left ventricular function in patients with acute myocardial infarction?”. Circulation. 100 (4): 339–45. PMID 10421592. Unknown parameter |month= ignored (help)
  6. ↑ Stone, GW.; Grines, CL.; Rothbaum, D.; Browne, KF.; O’Keefe, J.; Overlie, PA.; Donohue, BC.; Chelliah, N.; Vlietstra, R. (1997). “Analysis of the relative costs and effectiveness of primary angioplasty versus tissue-type plasminogen activator: the Primary Angioplasty in Myocardial Infarction (PAMI) trial. The PAMI Trial Investigators”. J Am Coll Cardiol. 29 (5): 901–7. PMID 9120173. Unknown parameter |month= ignored (help)
  7. ↑ Nicklas, JM.; Diltz, EA.; O’Neill, WW.; Bourdillon, PD.; Walton, JA.; Pitt, B. (1987). “Quantitative measurement of coronary flow during medical revascularization (thrombolysis or angioplasty) in patients with acute infarction”. J Am Coll Cardiol. 10 (2): 284–9. PMID 2955024. Unknown parameter |month= ignored (help)
  8. ↑ Iwakura, K.; Ito, H.; Nishikawa, N.; Hiraoka, K.; Sugimoto, K.; Higashino, Y.; Masuyama, T.; Hori, M.; Fujii, K. (1999). “Early temporal changes in coronary flow velocity patterns in patients with acute myocardial infarction demonstrating the no-reflow phenomenon”. Am J Cardiol. 84 (4): 415–9. PMID 10468079. Unknown parameter |month= ignored (help)
  9. ↑ “http://www.annualreviews.org/doi/abs/10.1146/annurev.fluid.29.1.399?journalCode=fluid”. Retrieved 13 November 2013. External link in |title= (help)


Template:WikiDoc Sources

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: ; Vanessa Cherniauskas, M.D. [2]