History
A 65-year-old man with ischemic dilated cardiomyopathy, already treated by stenting of the anterior interventricular coronary artery and then by coronary artery bypass graft surgery, received a dual-chamber implantable cardioverter-defibrillator (ICD) 4 years previously for primary prevention of sudden cardiac death. At that moment the electrocardiogram (ECG) showed an incomplete left bundle branch block (LBBB) with a QRS duration of less than 120 ms. The patient was later admitted to the hospital because of acute heart failure decompensation. During the last 6 months his functional capacity progressively declined (currently New York Heart Association [NYHA] class III) despite medical therapy optimization.
Comments
This patient showed progressive worsening of his clinical condition likely atributable to the underlying heart disease (coronary artery disease) and progression of ventricular conduction delay (LBBB on surface ECG).
Current Medications
The patient was taking torasemide 10 mg daily, bisoprolol 5 mg daily, spironolactone 25 mg daily, enalapril 10 mg twice daily, aspirin 100 mg daily, and insulin.
Current Symptoms
The patient was experiencing dyspnea at rest, orthopnea, and edema of the inferior extremities.
Physical Examination
Laboratory Data
Electrocardiogram
Findings
The ECG revealed a heart rate of 76 bpm, a sinus rhythm with a PR interval of 190 ms, and a complete LBBB with a QRS duration of 136 ms (Figure 32-1).
FIGURE 32-1
Echocardiography
Findings
The echocardiogram documented a dilated left ventricle (end-diastolic volume 210 mL) with a severe reduction of the ejection fraction (18%); moderate mitral and tricuspid regurgitation; restrictive mitral flow pattern; left atrium dilation (59 mm); moderate pulmonary arterial hypertension (60 mm Hg); and right ventricle with normal dimensions and function.
Catheterization
A coronary angiography was performed showing three-vessel disease with patency of all the coronary grafts (left internal mammary artery on anterior interventricular coronary artery, right internal mammary artery on right coronary artery, double venous grafts on circumflex artery).
Focused Clinical Questions and Discussion Points
Question
What would be the next step for the treatment of the heart failure in this patient?
Discussion
An upgrade to a resynchronization device is indicated. The patient already had a dual-chamber ICD for the treatment of ventricular arrhythmias. He had normal chronotropic competence with a preserved day–night variability, and the spontaneous QRS width was 136 ms with a LBBB pattern. The benefit of cardiac resynchronization therapy (CRT) in patients with heart failure with a QRS duration of 120 ms or greater, a LBBB pattern, and an ejection fraction of 35% or less has been demonstrated in many important multicenter trials, such as the Comparison of Medical Therapy, Pacing, and Defibrillation in Chronic Heart Failure (COMPANION)1 and Cardiac Resynchronization in Heart Failure (CARE-HF) studies.2 Their consistent results have been summarized in the European Society of Cardiology guidelines of 2013, with an indication of class I and level of evidence B (LBBB pattern, QRS 120-150 ms) for the patient described in this report.3
Question
Which position should be considered a target pacing site—a more apical position, a midvein position, or a basal position?
Discussion
A midvein or, better, basal position is the best choice. The impact of the left ventricular lead position on outcome in patients randomized to CRT defibrillator implant in the Multicenter Automatic Defibrillator Implantation Trial–Cardiac Resynchronization Therapy (MADIT-CRT)4 study has been reported. The study showed that left ventricular leads positioned in the apical region were associated with an unfavorable outcome, suggesting that this lead location should be avoided in CRT.
FIGURE 32-2
Intervention
After ICD removal, a 9-French introducer was placed in the left subclavian vein. Then a preshaped 8-French catheter (CPS DirectTM SL II Slittable Outer Guide Catheter with Integrated Valve, St. Jude Medical, St. Paul, Minn.) was used to cannulate the coronary sinus. However, a partial angiography of the coronary sinus was possible because of a prominent valve impeding visualization of the distal section of the coronary sinus. A large and long posterolateral vein presenting a very sharp take-off and a secondary 90-degree curve was visualized (Figure 32-2).
A preshaped inner catheter (CPS Aim SL Slittable Inner Catheter with Integrated Valve, St. Jude Medical) with a 90-degree angle was advanced into the guiding catheter supported by a 0.30-inch Terumo guide wire (Somerset, NJ), and both were gently advanced into the coronary sinus. A successful coronary sinus branch vein subselection was finally achieved. Then a 0.014-inch hydrophilic stiff guide wire (Whisper ES, Abbott, Abbott Park, Ill.) was placed distally into the coronary vein and looped into the same coronary vein (Figure 32-3). The extra-support guide wire was chosen to stretch the tortuous vein and to provide support for a preshaped left ventricular pacing electrode.
A four-pole preshaped electrode (Quartet, St. Jude Medical) was chosen to provide good mechanical stability while allowing significant pacing flexibility by electronic selection of the most appropriate pacing electrodes. The preshaped lead adapted well to the vein tortuosity and diameter; the tip of the lead was placed in the distal section of the vein. Each of the electrodes was tested, and phrenic nerve stimulation was obtained by pacing only the most distal electrode.
FIGURE 32-3
FIGURE 32-4
During the retraction maneuver of the guide wire, the distal part (about 4 cm) was suddenly broken off (Figure 32-4) while the proximal extremity of the fragment protruded into the lumen of the main body of the coronary sinus (Figure 32-5).
Question
What is the next step—leave the wire inside the venous system or try to remove it?
Perforation of the coronary vein may occur, but interference with sensing or pacing might be expected because the guide wire fragment is made of conducting material. Several tools are available for removal of foreign material from the circulation system. Retrieval of the guide wire was planned. An endovascular system device (Micro Elite Snare, Radius Medical Technologies, Aston, Mass.) was used that is specifically designed for the retrieval and manipulation of foreign bodies in the cardiovascular system (Figure 32-6). The ultra-small 0.014-inch profile permits delivery through catheters, eliminating the need for exchanges, reducing patient trauma, and saving valuable procedure time. The highly torqueable shaft design allows greater control and maneuverability for better access to distal targets, and the smooth helical loop blends the advantage of a smaller overall distal profile with a longer reach than right-angle loops. Moreover, the radiopaque loop enhances visualization and identification of the device’s capture area and sheath location.
FIGURE 32-5
FIGURE 32-6
FIGURE 32-7
FIGURE 32-8
The snare was advanced beyond the distal end of the broken wire (Figure 32-7) and pulled back to surround the wire fragment (Figure 32-8). Then, the snare with the captured guide wire fragment was carefully retrieved into the guiding catheter (Figure 32-9). After successful removal, a new guide wire was deployed and the quadripolar permanent pacing lead finally implanted (Figure 32-10). A chest radiograph shows the position of each electrode and the absence of pneumothorax (Figures 32-11 and 32-12).
FIGURE 32-9
FIGURE 32-10
Outcome
The patient was scheduled for a 1-month follow-up after device implantation. The sensed and paced and impedance parameters resulted in within-normal range, and the percentage of biventricular stimulation was 98%. The surgical wound was in a good state of healing and had no signs of infection. From the clinical point of view the patient reported a significant improvement in functional capacity (NYHA class II).
FIGURE 32-11
FIGURE 32-12
Selected References
1. Bristow M., Saxon L., Boehmer J. et al. for the Comparison of Medical Therapy, Pacing and Defibrillation in Heart Failure (COMPANION). Cardiac resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure. New Engl J Med. 2004;350:2140–2150.
2. Cleland J., Daubert J., Erdmann E. et al. for the CARE-HF study investigators. Longer-term effects of cardiac resynchronization therapy on mortality in heart failure [the Cardiac REsynchronization-Heart Failure (CARE-HF) trial extension phase]. Eur Heart J. 2006;27:1928–1932.
3. Brignole M., Auricchio A., Baron-Esquivias G. et al. 2013 ESC guidelines on cardiac pacing and cardiac resynchronization therapy. Europace. 2013;15(8):1070–1118.
4. Moss A., Hall W., Cannom D. et al. Cardiac-resynchronization therapy for the prevention of heart-failure events. N Engl J Med. 2009;361:1329–1338.
