Division of Cardiology, Section of Electrophysiology, Emory University, Atlanta, Georgia.
Medtronic plc, Mounds View, Minnesota.
J Cardiovasc Electrophysiol. 2020 Mar;31(3):712-717. doi: 10.1111/jce.14362. Epub 2020 Feb 3.
Infections of cardiac implantable electronic devices remain a prevalent health concern necessitating the advent of novel preventative strategies. Based on the observation that bacterial infections of the Micra transcatheter pacemaker device are extremely rare, we examine the effect of parylene coating on bacterial adhesion and growth.
Bacterial growth was compared on polyurethane coated, bare, or parylene coated titanium surfaces. Eight test samples per bacterial species and material combination were incubated with Staphylococcus Aureus or Pseudomonas aeruginosa for 24 hours and then assayed for bacterial growth. The surface contact angle was also characterized by measuring the angle between the tangent to the surface of a liquid droplet made with the surface of the solid sample.
The mean bacterial colony counts were significantly reduced for both parylene coated titanium versus bare samples (3.69 ± 0.27 and 4.80 ± 0.48 log[CFU/mL] respectively for S. aureus [P < .001] and 5.51 ± 0.27 and 6.08 ± 0.11 log[CFU/mL] respectively for P. aeruginosa [P < .001]), and for parylene coated titanium versus polyurethane samples (4.27 ± 0.42 and 5.40 ± 0.49 log[CFU/mL] respectively for S. aureus [P < .001] and 4.23 ± 0.42 and 4.84 ± 0.32 log[CFU/mL] respectively for P. aeruginosa [P = .006]). Parylene coated titanium samples had a higher contact angle compared with bare titanium, but lower compared with polyurethane (mean contact angle 87.5 ± 3.1 degrees parylene, 73.3 ± 3.7 degrees titanium [P < .001 vs parylene], and 94.8 ± 3.7 degrees polyurethane [P = .002 vs parylene]).
Parylene coating significantly reduced the ability of bacteria to grow in colony count assays suggesting that this could contribute to the reduction of bacterial infections of Micra transcatheter pacemakers.
心脏植入式电子设备的感染仍然是一个普遍存在的健康问题，这需要新的预防策略的出现。基于观察到 Micra 经导管起搏器设备的细菌感染极为罕见，我们研究了聚对二甲苯涂层对细菌粘附和生长的影响。
比较了细菌在涂有聚氨酯、裸露或涂有聚对二甲苯的钛表面上的生长情况。每种细菌和材料组合的 8 个测试样本与金黄色葡萄球菌或铜绿假单胞菌孵育 24 小时，然后检测细菌生长情况。表面接触角也通过测量与固体样品表面形成的液滴的切线与表面之间的角度来表征。
与裸露钛样品相比，聚对二甲苯涂层钛的细菌菌落计数均显著减少（金黄色葡萄球菌分别为 3.69±0.27 和 4.80±0.48log[CFU/mL] [P<.001]，铜绿假单胞菌分别为 5.51±0.27 和 6.08±0.11log[CFU/mL] [P<.001]），与涂有聚氨酯的钛相比，聚对二甲苯涂层钛的细菌菌落计数也显著减少（金黄色葡萄球菌分别为 4.27±0.42 和 5.40±0.49log[CFU/mL] [P<.001]，铜绿假单胞菌分别为 4.23±0.42 和 4.84±0.32log[CFU/mL] [P=.006]）。与裸露钛相比，聚对二甲苯涂层钛的接触角较高，但与聚氨酯相比，接触角较低（平均接触角 87.5±3.1 度聚对二甲苯，73.3±3.7 度钛[P<.001 对比聚对二甲苯]，94.8±3.7 度聚氨酯[P=.002 对比聚对二甲苯]）。
聚对二甲苯涂层显著降低了细菌在菌落计数试验中生长的能力，这表明这可能有助于减少 Micra 经导管起搏器的细菌感染。
