A “no-stopcock” technique for infant adenosine administration provides a complete bolus

2021 ◽  
Author(s):  
Lauren Bitterman ◽  
Kimberly Park ◽  
Olivia Paradis ◽  
Gigi Rodriguez ◽  
Deena I. Bengiamin ◽  
...  
Keyword(s):  
Adenosine Administration

Direct observation of epicardial coronary capillary hemodynamics during reactive hyperemia and during adenosine administration by intravital video microscopy

2005 ◽  
Vol 288 (3) ◽  
pp. H1437-H1443 ◽  
Author(s):  
Takahiko Kiyooka ◽  
Osamu Hiramatsu ◽  
Fumiyuki Shigeto ◽  
Hiroshi Nakamoto ◽  
Hiroyuki Tachibana ◽  
...  
Keyword(s):  
Blood Cell ◽  
Flow Velocity ◽  
Red Blood Cell ◽  
Capillary Flow ◽  
Reactive Hyperemia ◽  
Video Microscopy ◽  
Capillary Network ◽  
Arterial Flow ◽  
Canine Heart ◽  
Adenosine Administration

Using high-resolution intravital charge-coupled device video microscopy, we visualized the epicardial capillary network of the beating canine heart in vivo to elucidate its functional role under control conditions, during reactive hyperemia (RH), and during intracoronary adenosine administration. The pencil-lens video-microscope probe was placed over capillaries fed by the left anterior descending artery in atrioventricular-blocked hearts of open-chest, anesthetized dogs paced at 60–90 beats/min ( n = 17). In individual capillaries under control conditions, red blood cell flow was predominant during systole or diastole, indicating that the watershed between diastolic arterial and systolic venous flows is located within the capillaries. Capillary flow increased during RH and reached a peak flow velocity (2.1 ± 0.6 mm/s), twice as high as control (1.2 ± 0.5 mm/s), with enhancement of intercapillary cross-connection flow and enlargement of diameter (by 17%). With adenosine, capillary flow velocity significantly increased (1.8 ± 0.7 mm/s). However, the increase in volumetric capillary flow with adenosine estimated from red blood cell velocity and diameter was less than the increase in arterial flow, whereas that during RH was nearly equivalent to the increase in arterial flow. There was a time lag of ∼1.5 s for refilling of capillaries during RH, indicating their function as capacitance vessels. In conclusion, the coronary capillary network functions as 1) the major watershed between diastolic-dominant arterial and systolic-dominant venous flows, 2) a capacitor, and 3) a significant local flow amplifier and homogenizer of blood supply during RH, but with adenosine the increase in capillary flow velocity was less than the increase in arterial flow.

6114Indications, procedural parameters, complications and consequences of fractional flow reserve measurements in a multicenter cohort

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Troebs ◽  
M Marwan ◽  
L Gaede ◽  
J Feyrer ◽  
B Nazli ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Fractional Flow Reserve ◽  
Pressure Measurement ◽  
Patient Characteristics ◽  
Pressure Measurements ◽  
Fractional Flow ◽  
Coronary Syndrome ◽  
Flow Reserve ◽  
Adenosine Administration ◽  
Vessel Dissection

Abstract Background Determination of the Fractional Flow Reserve (FFR) has become part of routine clinical practice. Contemporary clinical use, consequences as well as complications in consecutive, large cohorts have not been thoroughly investigated. We report the results of the prospective Fractional Flow Reserve Fax Registry F (FR2) conducted in Germany. Purpose To systematically analyze indications, procedural parameters, complications and consequences of intracoronary pressure measurements in a large contemporary cohort. Methods Data of 2000 consecutive patients undergoing clinically indicated FFR, iFR or pd/pa measurements in 8 interventional centres in Germany were prospectively collected in a systematic fashion. Data included basic patient characteristics, procedural aspects of intracoronary pressure measurements, associated complications, visual stenosis degree, measurement results and treatment decisions. Results Mean patient age was 68±11 years, 73% of patients were male. Of all patients, 300 patients (15%) had an acute coronary syndrome (STEMI: 9; NSTEMI: 94; unstable angina: 197) and 1002 patients (50%) had undergone previous revascularization. A mean of 1.7±0.9 measurements were performed per patient, for which an average of 1.02 pressure wires were required (more than 1 wire in 64 patients). For all 3373 interrogated lesions, median stenosis degree was 60%. Vasodilator-free measurements were performed in 415/3373 cases (12%, iFR: 346; pd/pa: 69). For vasodilation, i.v. adenosine was used in 396 cases (13%), i.c. adenosine in 2628 cases (87%), and other drugs in 10 cases (0.3%). Measurement was performed before potential revascularization in 3232 cases (96%) and during or following PCI in 141 cases. In 2958 lesions analyzed by FFR, mean FFR was 0.87, with 588 FFR measurements ≤0.80 (19.8%). Median FFR values were higher for i.c than i.v. adenosine administration (0.88 vs. 0.84), but not significantly different after adjustment for stenosis degree. In 735 cases (20.2%), intracoronary pressure measurement was followed by revascularization measures, while in 2637 cases (79.8%), no revascularization or no further revascularization was performed. In 36 out of 117 stenoses visually estimated to be ≥90%, revascularization was deferred following pressure measurement (31%). In 75 out of 2958 lesions analyzed by FFR, revascularization was performed even though FFR was >0.80 (3%). Severe complications (vessel dissection or occlusion) occurred in 5 out of 2000 patients as a consequence of intracoronary pressure measurement, resulting in death of 1 patient. Conclusion In clinical practice, the majority of intracoronary pressure measurements are performed in stenoses of intermediate angiographic severity and revascularization is deferred in approximately 80% of lesions. Vasodilator-free measurements are infrequent and route of adenosine administration has no effect on results. Complication rate is low but not negligible. Acknowledgement/Funding Abbott Vascular

scholarly journals THE REGULATION OF PINOCYTOSIS IN MOUSE MACROPHAGES

1967 ◽  
Vol 125 (3) ◽  
pp. 457-466 ◽  
Author(s):  
Zanvil A. Cohn ◽  
Eileen Parks
Keyword(s):  
Large Numbers ◽  
Cytoplasmic Vesicles ◽  
Mouse Macrophages ◽  
Adenosine Phosphate ◽  
Adenosine Derivatives ◽  
Adenosine Administration ◽  
Pinocytic Vesicles

A study has been conducted on the influence of nucleosides and nucleotides to induce the formation of pinocytic vesicles in cultured mouse macrophages. Extremely high levels of cytoplasmic vesicles were found after exposure of macrophages to adenosine 5'-phosphate, ADP, and ATP. A limited vesicle response was obtained with adenosine 2'-. and 3'-phosphate, 3',5'-adenosine-phosphate, and deoxyadenosine 5'-phosphate. The di- and triphosphates of guanosine, inosine, cytidine, and uridine were stimulatory but much less active than the adenosine derivatives. Adenosine administration resulted in high levels of pinocytic activity whereas other nucleosides, including inosine, guanosine, cytidine, and uridine, yielded little or no stimulatory effect. Adenosine and its 5'-phosphates produced morphological effects on macrophages characterized by increased spreading, a thin, peripheral cytoplasmic veil with denser cores of oriented mitochondria and contraction of the centre-sphere region. Large numbers of pinosomes were seen in association with mitochondria-containing portions of the cytoplasm. The stimulatory effects of adenosine and ATP were rapid and involved the majority of cells in the culture. Adenosine was unable to reverse the pinocytosis inhibition produced by 2,4-DNP, whereas ATP raised vesicle counts to high levels. Possible mechanisms for these effects are discussed.

Adenosine inhibits postischemic leukocyte-endothelium interaction in postcapillary venules of the hamster

1991 ◽  
Vol 261 (3) ◽  
pp. H651-H655 ◽  
Author(s):  
D. Nolte ◽  
H. A. Lehr ◽  
K. Messmer
Keyword(s):  
Reperfusion Injury ◽  
Striated Muscle ◽  
Leukocyte Rolling ◽  
Red Cell ◽  
Microvascular Endothelium ◽  
Dorsal Skinfold Chamber ◽  
Chamber Model ◽  
Adenosine Administration ◽  
Radical Generation

The reduction of postischemic reperfusion injury by exogenous adenosine has been ascribed to reduced oxygen radical generation and adhesion of leukocytes to the vascular endothelium. To provide in vivo evidence for this concept we investigated the effects of adenosine (110 micrograms.kg-1.min-1 iv) on postischemic leukocyte-endothelium interaction in the dorsal skinfold chamber model in awake hamsters by intravital fluorescence microscopy. Leukocytes were stained in vivo with acridine orange and classified according to their interaction with the endothelium as nonadherent, rolling, or sticking leukocytes. In control animals, reperfusion after a 4-h pressure-induced ischemia to the striated muscle in the dorsal skinfold chamber elicited a marked increase in leukocyte rolling and sticking. This phenomenon was significantly attenuated in adenosine-treated animals 30 min after reperfusion. Postischemic changes in vessel diameters and red cell velocities were not affected by adenosine. The data suggest that systemic adenosine administration reduces reperfusion injury by the inhibition of postischemic leukocyte adherence to the microvascular endothelium.

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