Selection of radial artery for use as aortocoronary graft: preoperative assessment with Doppler ultrasound and digital photoplethysmography and surgical confirmation
(Portuguese PDF version)

Fanilda Souto Barros1, Sandra Maria Pontes1, Maria Alice Almeida Taylor2, Leonard Roelke Hermann3, Melchior Luiz Lima4

1. Vascular ultrasonographer. Angiolab - Laboratório de Diagnóstico Vascular, Vitória, ES, Brazil.
2. Surgeon and Vascular ultrasonographer. Angiolab - Laboratório de Diagnóstico Vascular, Vitória, ES, Brazil.
3. Surgeon and Vascular ultrasonographer. Professor of Angiology and Vascular Surgery, Universidade Federal do Espírito Santo (UFES), Vitória, ES, Brazil.
4. Cardiac surgeon, Universidade Federal do Espírito Santo (UFES), Vitória, ES, Brazil.

Correspondence:
Fanilda Souto Barros
Angiolab - Laboratório Vascular
Rua José Teixeira, 290
CEP 29055-310 - Vitória, ES
Brazil
E-mail: fanilda@bol.com.br

ABSTRACT

Introduction: With the increasing use of the radial artery as aortocoronary graft, it has become necessary to reevaluate the criteria used for preoperative selection of this vessel in myocardial revascularization surgery. The aim of this study was to employ the perioperative assessment performed by the cardiac surgeon to confirm the viability of the selected radial artery through two noninvasive methods: color Doppler ultrasound and digital photoplethysmography.

Methods: Between July 1998 and January 2000, 78 radial arteries and 78 ulnar arteries of 39 patients candidates for myocardial revascularization surgery were studied. The study was performed bilaterally using an ATL HDI 5000 ultrasound machine and a Parks Vascular Mini-Lab Model 1052-C. The radial artery was considered suitable to be used as aortocoronary graft when it fulfilled the following criteria: absence of atheromatosis or occlusion of the ipsilateral radial and ulnar arteries; internal diameter of the radial artery > 2.5 mm, assessed by color Doppler ultrasound; and presence of pulse wave in two or more digits during radial compression, assessed by photoplethysmography. The results of the exams were confirmed by the perioperative evaluation of the radial arteries.

Results: Of the 78 radial arteries studied, 66 (84.6%) were considered suitable to be used as a graft whereas 12 (15.4%) were considered unsuitable. Among the 39 patients studied, 24 (61.5%) underwent myocardial revascularization surgery with the use of the radial artery. The viability of the radial artery was evaluated perioperatively in all cases and confirmed preoperative findings determined by color Doppler ultrasound and photoplethysmography used to select the artery.

Conclusion: The authors conclude that the use of noninvasive tests - color Doppler ultrasound and photoplethysmography - to select radial artery for aortocoronary grafts is effective as confirmed by perioperative findings. The association of these two methods provides greater safety and a better surgical planning for each patient.

Key-words: radial artery, grafts, color Doppler ultrasound, photoplethysmography.
Palavras-chave: artéria radial, enxertos, ecocardiografia Doppler em cores, fotopletismografia.

J Vasc Br 2004;3(2):107-10

During many years, the internal saphenous vein was the best choice as an arterial substitute. First described by Favarolo et al.1 and still used by many cardiovascular surgeons in cases of obstructive atherosclerotic disease, the internal saphenous vein, however, is not the only alternative, perhaps not even the better. Later, the use of mammary artery (internal thoracic) with the same purpose was proposed by Kolessov et al.2

Carpentier et al.3 were the pioneers in employing the radial artery as a vascular substitutive in myocardial revascularization surgery. Initially, this technique presented bad results due to the spasm that is peculiar to this vessel. Years later, changes were introduced on the surgical technique, as well the association of drugs like calcium channel blockers, with the aim at reducing the incidence of vasospasms.4 These changes stimulated the reactivation of the use of this artery.

The use of artery as a graft has showed to be superior to the use of vein due to its similarity in caliber to the coronary, its wall composition, and its longer patency time.

In face of the frequent usage of radial artery as aortocoronary bypass and the excellent results showed by several authors,4,5 it has become necessary to reevaluate the criteria used in the preoperative selection of this vessel when the objective is to study patency, diameter size, presence or absence of atherosclerotic disease in the radial and ulnar arteries, and assess digital perfusion through maneuvers that simulate radial artery harvesting, avoiding, therefore, ischemic postoperative complications, as well as providing surgeons with information regarding the anatomic and functional state of the selected artery.

In relation to hand circulation, it is widely known that the irrigation is predominantly performed by the superficial palmar arch, with the ulnar artery playing the major role. The superficial palmar arch is called complete when there is a continuity of the arch, with blood supply coming through both radial and ulnar arteries. It is considered incomplete when there is no connection between the terminal branches of both arteries, in a way that, in such cases, radial artery harvesting may affect digital perfusion. According to Coleman et al.,6,7 the arch is complete in 78.5% of the population.

The advent of color Doppler (CD), a noninvasive vascular diagnostic technique, made possible to select which venous or arterial segment is suitable to be used as arterial substitute.8

The aim of this work is to evaluate the efficiency and utility of radial artery mapping with the use of CD combined with digital photoplethysmography in patients selected for myocardial revascularization surgery, confirming, through surgical evaluation, the findings obtained from preoperative noninvasive methods.

MATERIAL AND METHODS

From July 1998 to January 2000, 78 radial and 78 ulnar arteries of 39 patients were studied. Among the 39 patients, 27 were male and 12 were female. Age ranged from 42 to 84 years. Arterial mapping with CD, including subclavian, brachial, radial and bilateral ulnar arteries, was performed on ATL HDI 5000 scanner, with 7.5-Mhz linear transducers. The following parameters were analyzed:

  • investigation of atherosclerotic disease of the radial and ulnar arteries;

  • inner diameter size of the radial and ulnar arteries, obtained through ultrasound with the vessel cut in cross-section;

  • patency assessment of the vessel by color and pulsed Doppler ultrasound.
The digital photoplethysmography was performed using a Parks vascular Mini-Lab,model 1052-C. Pulse waves were obtained from all digits, with patient in seated position keeping the hand relaxed, and during compression of the radial artery

The radial artery was considered suitable to be used as aortocoronary bypass when it presented the following parameters:

  • patency assessed by CD (Figure 1);

  • absence of atheromatosis in the radial and ulnar arteries assessed by CD;

  • inner diameter of radial artery > 2.5 mm (Figure 2);

  • photoplethysmography showing the presence of pulse wave in all digits during compression of the ipsilateral radial artery.

click hereFigure 1 - Radial artery patency showed by color Doppler.

click hereFigure 2 - Radial artery diameter.

The parameters evaluated by the cardiac surgery team were direct visibility of the artery and caliber measurement of the vessel, using ogives of 1.5 mm and 3.0 mm diameter. These data were used to confirm the description of the ultrasonographic findings.

The maneuver employed by the vascular surgeon to evaluate the integrity of the superficial palmar arch and later correlation with the photoplethysmography consisted of a small incision in the radial artery for detection of retrograde flow that, when present, reassured that the digital circulation would be maintained after the radial artery harvesting.

RESULTS

Among the 78 arteries studied in 39 patients, 66 (84.6%) were considered suitable and feasible for harvesting for further use as aortocoronary graft.

Of the 66 radial arteries considered suitable in 32 patients, 24 were used as aortocoronary bypass. There was no disagreement between the preoperative assessment obtained through the noninvasive methods and the perioperative findings.

Twelve arteries (15.4%) were considered unsuitable.

Contra-indications for radial artery harvesting were due to the presence of atherosclerotic disease in the radial artery, showed by CD ultrasound, in two cases; the presence of atherosclerotic disease of the ulnar artery in three cases; brachial artery occlusion, showed by CD ultrasound in two cases; absence or decrease of pulse wave in at least two digits during compression of the ipsilateral radial artery, evaluated by photoplethysmography in five arteries, although CD evaluation showed normal radial and ulnar arteries, therefore, suggesting the presence of incomplete superficial palmar arch.

In three patients, the photoplethysmography could not be performed. In these cases, the mapping of the radial and ulnar artery with CD was sufficient to select the radial artery for aortocoronary bypass. The perioperative finding was in accordance with the CD result.

None of the patients showed postoperative ischemic phenomena.

COMMENTS

Considering the increasing use of the radial artery as aortocoronary graft, the technological progress of noninvasive methods for assessment and selection of vascular substitutive, the preoperative mapping of the internal saphenous vein with CD,9 and the satisfactory results obtained from previous studies develop by our vascular team in association with cardiovascular surgeons, we decided to follow the same line of reasoning, that is, the correlation between the findings of radial artery preoperative selection by CD and photoplethysmography with perioperative assessment of the viability of this vessel to be used as a graft.

The radial artery mapping using CD in combination with digital photoplethysmography has showed to be very useful for radial artery preoperative selection in myocardial revascularization surgery. The CD provides information about the anatomic state of the artery whereas the photoplethysmography allows an indirect evaluation of digital perfusion during compression of the radial artery, simulating its harvesting.

Aiming at selecting the radial artery for aortocoronary bypass, Kupinski et al.,10 using CD and photoplethysmography, evaluated 146 patients before they underwent myocardial revascularization surgery. In 22 patients, the radial artery was not used due to abnormalities that were showed by the CD, by the photoplethysmography, or by both.

The radial artery of 24 (61.5%) patients, out of 39, was used as aortocoronary graft. Contraindication for harvesting 12 (15.4%) radial arteries, due to bilateral involvement of the arteries, lead to changes in the surgical planning of two patients.

During one month postoperatively, all patients were interviewed. There was no complaint about the presence of ischemic phenomena.

Perioperative evaluation of the quality and viability of use of the radial artery considered suitable by noninvasive preoperative assessment was confirmed in all cases.

The preoperative assessment of the patient selected to undergo myocardial revascularization surgery, using noninvasive methodology, offers safe and reliable information regarding the arterial or venous segment to be used as a graft. It also allows a more efficient surgical planning, since it is possible to foresee the available options and the best choice for the patient, avoiding, therefore, unnecessary incisions in search of veins and arteries, increased surgical time, as well as postoperative complications.

CONCLUSION

The authors conclude that the selection of the radial artery for use as aortocoronary graft, assessed by two noninvasive tests - CD and photoplethysmography - has proved to be efficient, since the viability of the radial artery, selected through the combination of these two methods, was confirmed by perioperative evaluation. Having previous information on the viability of the radial artery for use as arterial substitute provides greater safety and better surgical planning for each patient.

REFERENCES

1. Favarolo RG. Saphenous vein graft in the surgical treatment of coronary artery disease: operative technique. J Thorac Cardiovasc Surg 1969;58:178-85.

2. Kolessov VI. Mammary artery-coronary anastomosis as a method of treatment for angina pectoris. J Thorac Cardiovasc Surg 1967;54:535-44.

3. Carpenteer A, Guermonprez JL, Deloche A, Frechette C, DuBost C. The aorta-to-coronary radial artery bypass graft. Ann Thorac Surg 1973;16:111-21.

4. Manasse E, Sperti, Suma H, et al. Use of the radial artery for myocardial revascularization. Ann Thorac Surg 1996;62:1076-83.

5. Costa F, Costa I, Poffo R, et al. Myocardial revascularization with the radial artery: a clinical and angiographic study. Ann Thorac Surg 1996;62:745-80.

6. Dean RH, Yao J, Brewster D. Current diagnosis and treatment in vascular surgery. New York: The McGraw-Hill Companies; 1995. p. 155-157.

7. Winkler J, Lohr J, Heam A. Evaluation of the radial artery for use in coronary artery bypass grafting. J Vasc Tech 1998;22:23-9.

8. Cousens KA, Altemus AP, Musson AM, Zwoulak RM. Utility of preoperative vein mapping. J Vasc Technol 1997;21:227-31.

9. Barros F, Pontes S, Lima M, et al. Mapeamento da safena interna com ecocolor Doppler no pré-operatório de cirurgia de revascularização miocárdica. Rev Bras Cir Cardiovasc 1999;14:303-7.

10. Kupinski A, Huang J, Khan A, et al. Noninvasive upper extremity arterial. J Vasc Technol 1998;22:187-91.


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