Last week, I tried to stent a calcified right coronary artery using radial access and a 6 Fr JR 4 guide. Predilatation was uneventful with a 2.5 mm balloon to 16 atm. However, the stent would not cross the lesion. Clockwise torque to more deeply intubate the artery provided insufficient back-up. A stiff buddy wire did not help. A GuideLiner extension catheter could not pass beyond the proximal right coronary without the guide backing out. I considered converting to a more aggressive Amplatz guide or to femoral access with an 8 Fr guide. Then I remembered reviewing the manuscript by Kwan et al published in this issue of the Journal of Invasive Cardiology.1 Kwan described several cases like mine, and solved the problem with a trick that was new to me. The predilatation balloon was passed into the artery to the lesion and inflated, anchoring the guide. Now the GuideLiner could be passed into the distal artery as far as the lesion, providing much better back-up. After removing the balloon, the stent now easily crossed the lesion and was deployed successfully. Post-deployment angiograms showed no dissection from passage of the GuideLiner.
Certainly I could have switched guides for a more aggressive bend, or converted to femoral access with an 8 Fr guide. However, this technique took only minutes, saved time, and prevented the risk of femoral access in an anticoagulated patient or the risk, however small, of using a guide with a more aggressive bend. I felt fortunate to have read Kwan’s manuscript and to have remembered the trick it described. It reminded me of the power of stories. More about that later.
Kwan et al’s report in this issue of the Journal includes 54 patients with “complex” lesions who underwent percutaneous coronary intervention (PCI) using an extension catheter to intubate the artery and provide superior back-up. They achieved success in 96% with no complications. They conclude that extension catheters are useful in PCI via the radial artery approach and may be considered as an “initial strategy” for difficult-to-stent lesions.
Does Kwan’s paper add anything new to the cardiology literature? Other investigators have reported series of successful cases performed using an extension catheter.2-10 Others have reported series of extension catheter cases that are free of complications2,5,8,10 and emphasized the need to deeply intubate the coronary artery with the extension catheter to achieve success.2,10 Finally, others have found that extension catheters are more effective than alternatives such as buddy wires, anchoring balloons deployed in side branches, or upsizing guide catheter size.4
Taken together, these previous reports allow several conclusions. First, extension catheters are generally successful. The above series have reported PCI success rates in complex anatomy using extension catheters in 70%-100% of cases. Second, extension catheters are generally safe. The most common complications are dissection of the vessel proximal to the target site, which can usually be safely stented. Finally, these findings apply to PCI with radial access, since most of these series have used radial access for most patients.
Kwan et al’s study confirms the conclusions from these previous reports. But what does it add that is new? For this operator, it was the new “trick” described above. When the GuideLiner cannot be passed deeply into the artery, it can be pulled deeper by anchoring a balloon at or just proximal to the lesion. Often, this improves back-up support sufficiently to deploy the stent. And that leads to the final conclusion of this editorial.
This is the era of big data and huge databases. Cardiology journals now routinely include studies with tens or hundreds of thousands of patients.11,12 These provide real-world data on patient groups so large that they can detect patterns not evident in smaller studies, and results can be widely generalized. These studies are useful when deciding how to treat groups of patients. Applying them to our patients benefits perhaps 1 patient in 30 or 300, depending on the number needed to treat. However, the application of “big data” studies to individual patients may be confused by conflicting safety data, flaws in trial design, or study inclusion/exclusion criteria that may prevent the study results from application to our particular patient.
In contrast, a story about a single patient and the “trick” that allowed successful completion of a procedure can be easily remembered and applied. While it may only benefit 1 patient, for that patient the benefit can be the difference between the success and failure of the procedure.
Thus, the final conclusion of this editorial relates to the power of the story in this, the era of big data. Big data may revolutionize research and prove invaluable to developing treatment protocols. But the case report still has value. It is often the practical knowledge of how an operator dealt with a specific problem in the past that can guide an interventionist now facing a difficult situation.
- Kwan TW, Diwan R, Ratcliffe JA, et al. The utility of extension catheters in transradial percutaneous coronary intervention. J Invasive Cardiol. 2015;27(1):28-32.
- Mamas MA, Eichhofer J, Hendry C, et al. Use of the Heartrail II catheter as a distal stent delivery device; an extended case series. EuroIntervention. 2009;5(2):265-271.
- Cola C, Miranda F, Vaquerizo B, Fantuzzi, A, Bruguera J. The GuideLiner catheter for stent delivery in difficult cases: tips and tricks. J Interv Cardiol. 2011;24(5):450-461.
- Zhang Q, Zhang RY, Kirtane AJ, et al. The utility of a 5-in-6 double catheter technique in treating complex coronary lesions via transradial approach: the DOCA-TRI study. EuroIntervention. 2012;8(7):848-854.
- Chan PH, Alegria-Barrero E, Foin N, et al. Extended use of the GuideLiner in complex coronary interventions. EuroIntervention. 2014 Jun 16. (Epub ahead of print].
- Dardas PS, Mezilis N, Ninios V, Tsikaderis D, Theofilogiannakos EK. The use of the GuideLiner catheter as a child-in-mother technique: an initial single-center experience. Heart Vessels. 2012;27(5):535-540. Epub 2011 Aug 25.
- Sambu N, Fernandez J, Shah NC, O’Kane P. The GuideLiner: an interventionist’s experience of their first 50 cases: the mostly good, rarely bad, beware of the ugly! Interv Cardiol. 2013;5(4):389-404.
- de Man FHAF, Birgelen C. Usefulness and safety of the GuideLiner catheter to enhance intubation and support of guide catheters: insights from the Twente GuideLiner registry. EuroIntervention. 2012;8(3):336-344.
- Kovacic JC, Sharma AB, Roy S, et al. GuideLiner mother-and-child guide catheter extension: a simple adjunctive tool in PCI for balloon uncrossable chronic yotal occlusions. J Intervent Cardiol. 2013;26(4):343-350.
- Farooq V, Mamas MA, Fath-Ordoubadi F, Fraser DG. The use of a guide catheter extension system as an aid during transradial percutaneous coronary intervention of coronary artery bypass grafts. Catheter Cardiovasc Interv. 2011;78(6):847-863. Epub 2011 Jun 7.
- Maddox TM, Stanislawski MA, Grunwald GK, et al. Nonobstructive coronary artery disease and risk of myocardial infarction. JAMA. 2014;312(17):1754-1763.
- Feldman DN, Swaminathan RV, Kaltenbach LA, et al. Adoption of radial access and comparison of outcomes to femoral access in percutaneous coronary intervention: an updated report from the National Cardiovascular Data Registry (2007–2012). Circulation. 2013;127(23):2295-2306.
From the Department of Cardiology, Geisinger Medical Center, Danville, Pennsylvania.
Disclosure: The author has completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The author reports no conflicts of interest regarding the content herein.
Address for correspondence: James C. Blankenship, MD, MSc, Geisinger Medical Center, 100 N. Academy Avenue, Danville PA 17822. Email: firstname.lastname@example.org