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Transfemoral catheterization of the coronary sinus by Doppler catheters for determination of coronary flow reserve
1090
Brief Communication-s
American
Transfemoral catheterization of the coronary sinus by Doppler catheters for determination of coronary flow reserve Jiirgen Berndt
Tebbenjohanns, MD, Jobst Nitsch, Liideritz, MD. Bonn, Germany
MD, and
Coronary flow reserve is a useful index of the vasodilator capacity of the coronary circulation. This measurement has been used to assess the hemodynamic significance of coronary stenosis, to evaluate the results of coronary angioplasty and coronary bypass surgery, as well as to study patients with syndrome X and after orthotopic heart transp1antation.l In previous studies the Doppler catheter technique has been widely applied for determination of coronary flow reserve in individual coronary arteries.2 The coronary sinus thermodilution technique is the most frequently applied approach for studying coronary flow in humans. But this method has some limitations that are not appreciated: phasic coronary flow or rapid changes in mean flow cannot be assessed and positioning the catheter in the coronary sinus may be difficult and time-consuming. These limitations do not apply when using Doppler catheters that have not yet been used for determination of coronary sinus blood flow. We therefore simultaneously measured coronary sinus blood flow using continuous thermodilution and Doppler catheters. We studied seven patients (age: 53 -t 7 years) (six men and one woman) who were referred to the catheterization laboratory for coronary angiography. All had a normal anFrom Reprint University
the Department
of Cardiology,
University
of Bonn.
requests: Jiirgen Tebbenjohanns. MD, Department of Bonn, Sigmund-Freud Strasse 25, 5300 Bonn
414134630
of Cardiology, 1, Germany.
April 1992 Heart Journal
giogram and a normal left ventricular ejection fraction (75 + 10%). At the time of testing none of the patients were receiving any cardiac medication. An 8F coronary guiding catheter (Amplatz 2, Medtronic Interventional Vascular Inc., Danvers, Mass.) was inserted into the right femoral vein and was advanced under fluoroscopic control into the coronary sinus ostium. Then an 0.014-inch coronary angioplasty guide wire was advanced into the coronary sinus. A 3F 20 MHz Doppler catheter (Floscan, Medtronic Inc., Minneapolis, Minn.) was advanced over the guide wire into the coronary sinus and was positioned to obtain a high-quality phasic signal of the coronary sinus blood flow velocity.3 The pulsed Doppler velocimeter (Bioengineering, University of Iowa) was range-gated to maximize the amplitude of the mean coronary blood flow velocity signal. A 7F thermodilution catheter (Wilton Webster Manufactoring Co., Altadena, Calif.) was introduced from the right antecubital vein and was placed into the coronary sinus (Fig. 1). A room temperature 5 % solution of dextrose was infused through the thermodilution catheter at a rate of 50 ml/min, and coronary sinus blood flow was calculated according to the formula of Ganz et a1.4 Phasic and mean coronary blood flow velocity, the coronary sinus blood flow volume obtained from the thermodilution catheter, heart rate, and the electrocardiogram were continuously recorded on a multichannel recorder. After measurements of the resting coronary sinus blood flow velocity and the coronary sinus blood flow volume, 0.5 mg/kg (10 mg/min) of dipyridamole was hand injected into the right femoral vein. The resultant increase in coronary sinus blood flow volume was recorded over 10 minutes. Coronary flow reserve was calculated as the quotient of the peak flow velocity (peak flow volume) after intravenous dipyridamole and t.he resting flow velocity (resting flow volume). During intravenous dipyridamole infusion, systolic and diastolic arterial pressure decreased from 125 2 10 to
Fig. 1. Transfemoral catheterization of the coronary sinus for determination of coronary flow reserve. A coronary guiding catheter is advanced from the right femoral vein in the coronary sinus ostium. A Doppler catheter is positioned through the guiding catheter in the coronary sinus for determination of blood flow velocity (arrow). Simultaneously, coronary sinus blood flow volume is measured by a thermodilution catheter (arrowhead). A pacemaker electrode is placed in the apex of the right ventricle.
Volume Number
123 4, Part 1
Brief Coriznunications
1091
CFR (Thermodilution) 3109
i 13
23
2,o
CFR (Do&$
Fig. 2. Determination of coronary flow reserve (CFR) assessed with thermodilution and Doppler catheters after administration of 0.5 mg/kg dipyridamole intravenously. Changes in coronary sinus blood flow velocity assessed with the Doppler catheter were highly correlated with simultaneously measured changes in blood flow volume determined by thermodilution.
115 ? 8 mm Hg and from 79 ? 9 to 74 k 8 mm Hg respectively (p < 0.05). Heart rate increased from 90 beats/min to 99 beats/min (p < 0.05). Intravenous dipyridamole resulted in an average Z.l-fold increase in resting flow velocity (range 1.8 to 2.4 times resting velocity) determined by the Doppler catheter. Similarly, the coronary sinus blood flow volume amounted to 2.2-fold resting flow (range 1.9 to 2.7 times resting flow volume) calculated by thermodilution (Fig. 2). The correlation coefficient was 0.88. Since its introduction in 1971 by Ganz et al.,4 the thermodilution technique has been widely applied to provide safe measurements of the coronary sinus blood flow volume in humans.5 Using thermodilution, this technique is able to make regional measurements in the great cardiac vein that reflect the anterior left ventricular drainage and the more proximal coronary sinus, which reflects the anterior and posterolateral left ventricular drainage. The inability to obtain on-line flow measurements and to assess rapid changes in flow has prevented characterization of hemodynamics during angioplasty procedures or evaluation of characteristics of coronary vasodilators. Furthermore, the technique is often time-consuming because the catheter has to be introduced from the antecubital or subclavian vein. Another limitation of the method is the need of relatively high amounts of indicator. Measurements of phasic coronary blood flow velocity and coronary flow reserve in individual coronary arteries have been done by Doppler catheters. The Doppler catheters are more than two times smaller than the thermodilution catheter and they do not cause coronary obstruction in major coronary vessels.’ One deficiency is present when Doppler technology is used. With the Doppler catheter only changes in velocity can be obtained, whereas determination.of absolute flow is difficult because measurement of the diameter of the vessel is necessarily required. The purpose of the present study was
to compare the accuracy of coronary flow reserve determination obtained by Doppler catheters measuring coronary sinus blood flow velocity with the continuous sinus thermodilution technique.6 The measurements provided a good correlation of 0.88 using these techniques simultaneously. In conclusion, measurement of coronary sinus blood flow velocity by Doppler catheters yields promising results. The technique permits continuous on-line recording of instantaneous phasic flow velocity. Consequently, the effect of pharmacologic agents and the angioplasty procedure, which cause rapid changes in coronary circulation, can be studied. The technique is safe, simple to apply, and inexpensive. It is an encouraging adjunct that can be used as an alternative to the thermodilution method for some special investigations-e.g., the determination of coronary flow reserve. REFERENCES
1. Marcus ML, Wilson RF, White CW. Methods of measurement of myocardial blood flow: a critical review. Circulation 1987;76:245-53. 2. Wilson RF, Laughlin DE, Ackell PH, et al. Transluminal, subselective measurement of coronary artery blood flow velocity and the vasodilator reserve in man. Circulation 1985; 72232-92. 3. Nitsch J, Tebbenjohanns J, Liideritz B. Continuous monitoring of the coronary perfusion during percutaneous transluminal coronary angioplasty of the left anterior descending artery. J Intervent Cardiol 1989;2:205-10. 4. Ganz W, Tamura K, Marcus HS, Donoso R, Yoshida S, Swan HJC. Measurement of the coronary sinus blood flow by continuous thermodilution in man. Circulation 1971;44:181-95. 5. Bairn DS, Rothman MT, Harrison DC. Improved catheter for regional coronary sinus flow and metabolic studies. Am J Cardiol 1980;46:997-1000. 6. Tebbenjohanns J, Nitsch J, Liideritz B. Measurement of coronary sinus blood flow and coronary flow reserve by Doppler catheters versus continuous Heart J 1990;11:13.
thermodilution
[Abstract].
Eur
Brief Communication-s
American
Transfemoral catheterization of the coronary sinus by Doppler catheters for determination of coronary flow reserve Jiirgen Berndt
Tebbenjohanns, MD, Jobst Nitsch, Liideritz, MD. Bonn, Germany
MD, and
Coronary flow reserve is a useful index of the vasodilator capacity of the coronary circulation. This measurement has been used to assess the hemodynamic significance of coronary stenosis, to evaluate the results of coronary angioplasty and coronary bypass surgery, as well as to study patients with syndrome X and after orthotopic heart transp1antation.l In previous studies the Doppler catheter technique has been widely applied for determination of coronary flow reserve in individual coronary arteries.2 The coronary sinus thermodilution technique is the most frequently applied approach for studying coronary flow in humans. But this method has some limitations that are not appreciated: phasic coronary flow or rapid changes in mean flow cannot be assessed and positioning the catheter in the coronary sinus may be difficult and time-consuming. These limitations do not apply when using Doppler catheters that have not yet been used for determination of coronary sinus blood flow. We therefore simultaneously measured coronary sinus blood flow using continuous thermodilution and Doppler catheters. We studied seven patients (age: 53 -t 7 years) (six men and one woman) who were referred to the catheterization laboratory for coronary angiography. All had a normal anFrom Reprint University
the Department
of Cardiology,
University
of Bonn.
requests: Jiirgen Tebbenjohanns. MD, Department of Bonn, Sigmund-Freud Strasse 25, 5300 Bonn
414134630
of Cardiology, 1, Germany.
April 1992 Heart Journal
giogram and a normal left ventricular ejection fraction (75 + 10%). At the time of testing none of the patients were receiving any cardiac medication. An 8F coronary guiding catheter (Amplatz 2, Medtronic Interventional Vascular Inc., Danvers, Mass.) was inserted into the right femoral vein and was advanced under fluoroscopic control into the coronary sinus ostium. Then an 0.014-inch coronary angioplasty guide wire was advanced into the coronary sinus. A 3F 20 MHz Doppler catheter (Floscan, Medtronic Inc., Minneapolis, Minn.) was advanced over the guide wire into the coronary sinus and was positioned to obtain a high-quality phasic signal of the coronary sinus blood flow velocity.3 The pulsed Doppler velocimeter (Bioengineering, University of Iowa) was range-gated to maximize the amplitude of the mean coronary blood flow velocity signal. A 7F thermodilution catheter (Wilton Webster Manufactoring Co., Altadena, Calif.) was introduced from the right antecubital vein and was placed into the coronary sinus (Fig. 1). A room temperature 5 % solution of dextrose was infused through the thermodilution catheter at a rate of 50 ml/min, and coronary sinus blood flow was calculated according to the formula of Ganz et a1.4 Phasic and mean coronary blood flow velocity, the coronary sinus blood flow volume obtained from the thermodilution catheter, heart rate, and the electrocardiogram were continuously recorded on a multichannel recorder. After measurements of the resting coronary sinus blood flow velocity and the coronary sinus blood flow volume, 0.5 mg/kg (10 mg/min) of dipyridamole was hand injected into the right femoral vein. The resultant increase in coronary sinus blood flow volume was recorded over 10 minutes. Coronary flow reserve was calculated as the quotient of the peak flow velocity (peak flow volume) after intravenous dipyridamole and t.he resting flow velocity (resting flow volume). During intravenous dipyridamole infusion, systolic and diastolic arterial pressure decreased from 125 2 10 to
Fig. 1. Transfemoral catheterization of the coronary sinus for determination of coronary flow reserve. A coronary guiding catheter is advanced from the right femoral vein in the coronary sinus ostium. A Doppler catheter is positioned through the guiding catheter in the coronary sinus for determination of blood flow velocity (arrow). Simultaneously, coronary sinus blood flow volume is measured by a thermodilution catheter (arrowhead). A pacemaker electrode is placed in the apex of the right ventricle.
Volume Number
123 4, Part 1
Brief Coriznunications
1091
CFR (Thermodilution) 3109
i 13
23
2,o
CFR (Do&$
Fig. 2. Determination of coronary flow reserve (CFR) assessed with thermodilution and Doppler catheters after administration of 0.5 mg/kg dipyridamole intravenously. Changes in coronary sinus blood flow velocity assessed with the Doppler catheter were highly correlated with simultaneously measured changes in blood flow volume determined by thermodilution.
115 ? 8 mm Hg and from 79 ? 9 to 74 k 8 mm Hg respectively (p < 0.05). Heart rate increased from 90 beats/min to 99 beats/min (p < 0.05). Intravenous dipyridamole resulted in an average Z.l-fold increase in resting flow velocity (range 1.8 to 2.4 times resting velocity) determined by the Doppler catheter. Similarly, the coronary sinus blood flow volume amounted to 2.2-fold resting flow (range 1.9 to 2.7 times resting flow volume) calculated by thermodilution (Fig. 2). The correlation coefficient was 0.88. Since its introduction in 1971 by Ganz et al.,4 the thermodilution technique has been widely applied to provide safe measurements of the coronary sinus blood flow volume in humans.5 Using thermodilution, this technique is able to make regional measurements in the great cardiac vein that reflect the anterior left ventricular drainage and the more proximal coronary sinus, which reflects the anterior and posterolateral left ventricular drainage. The inability to obtain on-line flow measurements and to assess rapid changes in flow has prevented characterization of hemodynamics during angioplasty procedures or evaluation of characteristics of coronary vasodilators. Furthermore, the technique is often time-consuming because the catheter has to be introduced from the antecubital or subclavian vein. Another limitation of the method is the need of relatively high amounts of indicator. Measurements of phasic coronary blood flow velocity and coronary flow reserve in individual coronary arteries have been done by Doppler catheters. The Doppler catheters are more than two times smaller than the thermodilution catheter and they do not cause coronary obstruction in major coronary vessels.’ One deficiency is present when Doppler technology is used. With the Doppler catheter only changes in velocity can be obtained, whereas determination.of absolute flow is difficult because measurement of the diameter of the vessel is necessarily required. The purpose of the present study was
to compare the accuracy of coronary flow reserve determination obtained by Doppler catheters measuring coronary sinus blood flow velocity with the continuous sinus thermodilution technique.6 The measurements provided a good correlation of 0.88 using these techniques simultaneously. In conclusion, measurement of coronary sinus blood flow velocity by Doppler catheters yields promising results. The technique permits continuous on-line recording of instantaneous phasic flow velocity. Consequently, the effect of pharmacologic agents and the angioplasty procedure, which cause rapid changes in coronary circulation, can be studied. The technique is safe, simple to apply, and inexpensive. It is an encouraging adjunct that can be used as an alternative to the thermodilution method for some special investigations-e.g., the determination of coronary flow reserve. REFERENCES
1. Marcus ML, Wilson RF, White CW. Methods of measurement of myocardial blood flow: a critical review. Circulation 1987;76:245-53. 2. Wilson RF, Laughlin DE, Ackell PH, et al. Transluminal, subselective measurement of coronary artery blood flow velocity and the vasodilator reserve in man. Circulation 1985; 72232-92. 3. Nitsch J, Tebbenjohanns J, Liideritz B. Continuous monitoring of the coronary perfusion during percutaneous transluminal coronary angioplasty of the left anterior descending artery. J Intervent Cardiol 1989;2:205-10. 4. Ganz W, Tamura K, Marcus HS, Donoso R, Yoshida S, Swan HJC. Measurement of the coronary sinus blood flow by continuous thermodilution in man. Circulation 1971;44:181-95. 5. Bairn DS, Rothman MT, Harrison DC. Improved catheter for regional coronary sinus flow and metabolic studies. Am J Cardiol 1980;46:997-1000. 6. Tebbenjohanns J, Nitsch J, Liideritz B. Measurement of coronary sinus blood flow and coronary flow reserve by Doppler catheters versus continuous Heart J 1990;11:13.
thermodilution
[Abstract].
Eur