Intramyocardial transplantation of autologous CD34+ stem cells for intractable angina: a phase I/IIa double-blind, randomized controlled trial.

BACKGROUND: A growing population of patients with coronary artery disease experiences angina that is not amenable to revascularization and is refractory to medical therapy. Preclinical studies have indicated that human CD34+ stem cells induce neovascularization in ischemic myocardium, which enhances perfusion and function. METHODS AND RESULTS: Twenty-four patients (19 men and 5 women aged 48 to 84 years) with Canadian Cardiovascular Society class 3 or 4 angina who were undergoing optimal medical treatment and who were not candidates for mechanical revascularization were enrolled in a double-blind, randomized (3:1), placebo-controlled dose-escalating study. Patients received granulocyte colony-stimulating factor 5 microg x kg(-1) x d(-1) for 5 days with leukapheresis on the fifth day. Selection of CD34+ cells was performed with a Food and Drug Administration-approved device. Electromechanical mapping was performed to identify ischemic but viable regions of myocardium for injection of cells (versus saline). The total dose of cells was distributed in 10 intramyocardial, transendocardial injections. Patients were required to have an implantable cardioverter-defibrillator or to temporarily wear a LifeVest wearable defibrillator. No incidence was observed of myocardial infarction induced by mobilization or intramyocardial injection. The intramyocardial injection of cells or saline did not result in cardiac enzyme elevation, perforation, or pericardial effusion. No incidence of ventricular tachycardia or ventricular fibrillation occurred during the administration of granulocyte colony-stimulating factor or intramyocardial injections. One patient with a history of sudden cardiac death/ventricular tachycardia/ventricular fibrillation had catheter-induced ventricular tachycardia during mapping that required cardioversion. Serious adverse events were evenly distributed. Efficacy parameters including angina frequency, nitroglycerine usage, exercise time, and Canadian Cardiovascular Society class showed trends that favored CD34+ cell-treated patients versus control subjects given placebo. CONCLUSIONS: A randomized trial of intramyocardial injection of autologous CD34+ cells in patients with intractable angina was completed that provides evidence for feasibility, safety, and bioactivity. A larger phase IIb study is currently under way to further evaluate this therapy.

The acute phase reactant, fibrinogen, as a guide to plasma exchange therapy for acute Guillain-Barré syndrome.

The Guillian Barré syndrome is an acute inflammatory disorder for which plasma exchange is effective treatment. Up to 10% relapse after plasma exchange suggesting that treatment sometimes finishes before disease activity has resolved. We studied whether plasma fibrinogen, an inflammatory marker, might be used to determine when to discontinue plasma exchange in patients with acute Guillain-Barré syndrome. We conducted a post-hoc analysis of apheresis database and hospital records of patients treated with plasma exchange for acute Guillain-Barré syndrome during 1999-2004. Data were analyzed from 28 patients who underwent a total of 29 courses of plasma exchange for acute Guillain-Barré syndrome. The mean (+/-SD) plasma fibrinogen concentration was 422.5 (+/-96.4) mg/dl at the time of presentation and, in 17 of the 29, it was above 400 mg/dl (reference range 200-400). Twenty of the 21 patients whose fibrinogen fell by more than 30% from baseline by the time of the final plasma exchange treatment had neurological improvement. There was improvement in only 3 of the 8 instances where fibrinogen decreased by less than 30% by the end of plasma exchange therapy. A > or =30% decrease in fibrinogen by the conclusion of plasma exchange was significantly associated with sustained neurological improvement (P = 0.0025). The plasma fibrinogen level appears to reflect disease activity in acute Guillain-Barré syndrome. A <30% fall in fibrinogen level despite plasma exchange may indicate the need to continue plasma exchange to maximize the benefit of treatment or minimize the risk of relapse. Therapeutic plasma exchange need not be extended when plasma fibrinogen remains > or =30% below its level at presentation by the time of the final planned plasma exchange procedure.

Safety and efficacy of peripheral blood progenitor cell mobilization and collection in patients with advanced coronary heart disease.

Information on the safety of mobilization and collection of peripheral blood progenitor cells (PBPC) in patients with advanced coronary heart disease (CHD) is limited. We report herein our early experience with patients participating in a Phase I trial of injection of autologous CD 34(+) cells into threatened, ischemic myocardium for neovascularization and symptom relief in patients with chronic refractory myocardial ischemia. All patients had advanced inoperable CHD despite the best medical therapy. Granulocyte colony stimulating factor (G-CSF, 5 microg/kg/day) was administered subcutaneously for 5 days for mobilization of CD34(+) cells into the peripheral blood. PBPCs were collected in the outpatient apheresis suite on day 5. Nine patients from our institution were evaluable. Adverse effects of mobilization included: increase in frequency and/or intensity of angina in 8 patients (88.8%); bone pain in 7 patients (77.7%); headaches in 4 patients (44.4%); 2 patients (22%) were hospitalized. Collection phase toxicities included: tingling in 5 patients (55.5%) and angina in 3 patients (33%). All procedures were completed without new myocardial infarction, congestive heart failure, or death. The median peripheral blood CD34(+) cell count on day 5 of G-CSF was 21 cells/microl (range 10-40 cells/microl). A median of 1.65 x 10(6) CD34(+) cells/kg (range: 0.13-3.0 x 10(6)/kg) were harvested. We conclude that mobilization and collection of PBPC in patients with advanced CHD can be safely performed as an outpatient procedure. Apheresis professionals should be aware of the intensity and frequency of angina in this patient population.

Long-term therapeutic plasma exchange in the outpatient setting using an implantable central venous access device.

We presented the results of our prospective trial of the Bard CathLink 20 in outpatient therapeutic plasma exchange in May 2000. Since the close of that study, three of the original subjects and one additional subject have received continuous outpatient treatment using the device. We report herein on its long-term use. Four patients with demyelinating polyneuropathy underwent outpatient plasma exchange of 1-1 1/4 plasma volumes using Bard CathLink 20 venous access devices for up to 2 1/2 years. Treatment schedules varied according to the status of the patient's neuropathy. Four men (age 59, 60, 76, 79) underwent 55, 56, 38, and 41 plasma exchanges over 18.5, 18, 20, and 38.5 months, respectively, all in the outpatient setting. Ninety-one percent were completed in <150 min (mean 120 +/- 28 min) with 3,783 +/- 314 ml of plasma removed. Mean access flow rates were approximately 70 +/- 11 ml/min. Plasma flow rates were approximately 38 +/- 6 ml/min. (During our original 6-month prospective trial, access and plasma flow rates were approximately 54 and 32 ml/min, respectively). There were no adverse effects resulting from use of the CathLink and no hospitalizations were needed for plasma exchange. Pressure alarms were infrequent. Access and plasma flow rates achieved with the CathLink 20 have increased by about 30 and 16%, respectively, with long-term use. The conclusion from our prospective trial of this device, that it could conveniently be used for long-term outpatient plasma exchange, is supported by our follow-up experience.