(312 days)
The Micro Therapeutics Thrombolytic Brush Catheter is intended for percutaneous dissolution of acute thrombus (i.e., less than two weeks old) located in artificial arteriovenous (A-V) grafts. The Thrombolytic Brush Catheter is designed to augment the area of interface between clot and pharmacologic agent by simultaneous thrombolysis and clot maceration. Clinical studies demonstrate effective dissolution of thrombus in A-V grafts when this product is used in conjunction with urokinase. The Thrombolytic Brush Catheter is not intended for use in native vessels. The device should not be used on patients with a history of significant pulmonary disease or pulmonary hypertension.
The Micro Therapeutics Thrombolytic Brush Catheter is intended for the percutaneous dissolution of thrombus located in arteriovenous (A-V) grafts. The Micro Therapeutics Thrombolytic Brush Catheter is designed to augment the area of interface between clot and pharmacologic agent by simultaneous thrombolysis and clot maceration. The integral system utilizes a catheter with proximal Y-connector, a soft nylon brush attached to a stainless steel flexible drive cable, and a hand-held battery-powered motor drive.
Here's a breakdown of the acceptance criteria and study details for the Micro Therapeutics Thrombolytic Brush Catheter and Motor Drive, based only on the provided text.
1. Table of Acceptance Criteria and Reported Device Performance
The provided text does not explicitly state pre-defined acceptance criteria with numerical targets. Instead, the "Summary of Clinical Trials" table presents various metrics of device performance for both the Thrombolytic Brush Catheter and a control group (pulse-spray infusion) and then performs statistical comparisons. The conclusion states that the clinical data "demonstrate the Thrombolytic Brush Catheter is a safe, effective and rapid alternative to pulse-spray thrombolysis." This implies that showing superiority or non-inferiority to the control group on various metrics was the implicit acceptance criteria.
| Parameter | Thrombolytic Brush Catheter (Performance) | Pulse-Spray Infusion (Control) | Statistical Comparison | Implied Acceptance Criteria (Vs. Control) |
|---|---|---|---|---|
| Duration of lytic procedure | 17 minutes | 28 minutes | Significant (p=.0001) | Shorter duration |
| Residual thrombus after lytic procedure | 6.5% | 25.5% | Significant (p=.0001) | Less residual thrombus |
| Urokinase dose used | 215,435 Units | 455,882 Units | Significant (p=.0001) | Lower urokinase dose |
| Heparin dose used | 2,570 Units | 4,926 Units | Significant (p=.0001) | Lower heparin dose |
| Acute success of lytic procedure (Graft patent within 30 minutes) | 42/43 (98%) | 15/35 (43%) | Significant (p=.0001) | Higher acute success rate |
| Stenotic lesion visualized | 41/41 (100%) | 33/33 (100%) | Not Significant (p=1.000) | Comparable visualization |
| Thrombectomy performed to remove residual thrombus | 14/41 (34%) | 14/33 (42%) | Not Significant (p=.481) | Comparable need for thrombectomy |
| PTA performed to treat stenotic lesion | 41/41 (100%) | 32/32 (100%) | Not Significant (p=1.000) | Comparable need for PTA |
| Residual thrombus after thrombectomy and/or PTA | 2.2% | 1.6% | Not Significant (p=.6607) | Comparable final residual thrombus (though slightly higher for device, p not significant) |
| Duration of entire procedure | 70 minutes | 84 minutes | Not Significant (p=.1735) | Comparable total procedure duration (though shorter for device, p not significant) |
| Procedural success after all interventions (Graft patent, no major complications) | 39/43 (91%) | 34/35 (97%) | Not Significant (p=.621) | Comparable overall procedural success (though slightly lower for device, p not significant) |
| Successful dialysis after all interventions | 34/39 (87%) | 30/34 (88%) | Lifetable analysis: Not significant | Comparable successful dialysis (though slightly lower for device, lifetable analysis not significant) |
| Primary Patency at 3 months | 16/38 (42%) | 15/31 (48%) | Lifetable analysis: Not significant | Comparable primary patency at 3 months (though slightly lower for device, lifetable analysis not significant) |
| Failures within 3 months | 22/38 (58%) | 16/31 (52%) | Lifetable analysis: Not significant | Comparable failure rate at 3 months (though slightly higher for device, lifetable analysis not significant) |
| Primary Patency at 4½ months | 14/38 (37%) | 14/30 (47%) | Lifetable analysis: Not significant | Comparable primary patency at 4.5 months (though slightly lower for device, lifetable analysis not significant) |
| Failures within 4½ months | 24/38 (63%) | 16/30 (53%) | Lifetable analysis: Not significant | Comparable failure rate at 4.5 months (though slightly higher for device, lifetable analysis not significant) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: 81 patients in total, with 45 randomized to the Thrombolytic Brush Catheter treatment group and 36 to the pulse-spray infusion control group. For analysis, these translated to 43 grafts treated in the device group and 35 in the control group for some metrics, with some variations due to no follow-up or missing data for specific parameters.
- Data Provenance: Prospective, randomized clinical trial conducted at five institutions in the United States.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not explicitly state the number of experts or their qualifications used to establish ground truth for the clinical trial data. The assessment of "residual thrombus" and "patency" would typically involve physician judgment (likely interventional radiologists or nephrologists involved in AV graft management), but specifics are not provided.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method (e.g., 2+1, 3+1) for the clinical trial results. Data would have been collected by the investigators at each of the five institutions.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve With AI vs Without AI Assistance
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This study is for a medical device (catheter and motor drive) used by clinicians, not an AI-based diagnostic or imaging interpretation tool. Therefore, the concept of human readers improving with AI assistance is not applicable here.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
No, this question is not applicable. The device is a physical catheter and motor drive, not an algorithm. Its performance inherently requires human operation.
7. The Type of Ground Truth Used
The ground truth used in the clinical trial was primarily clinical outcomes and measurements as assessed by the treating physicians and follow-up. This included:
- Measurement of residual thrombus.
- Assessment of graft patency (ability to dialyze).
- Duration of procedures.
- Dosages of pharmacological agents.
- Incidence of interventions like thrombectomy and PTA.
- Follow-up data on primary patency and failures.
These are clinical observations and measurements, not pathology reports or a separate expert consensus on images (as would be typical for an imaging AI device).
8. The Sample Size for the Training Set
This study involves a medical device, not a machine learning model, so there is no concept of a "training set" in the context of algorithm development. The development process would have involved engineering design, in vitro testing, and animal studies.
9. How the Ground Truth for the Training Set Was Established
As there is no training set for an algorithm, this question is not applicable. For general device development, "ground truth" (e.g., for design validation) would be established through engineering specifications, validated test methods (in vitro), and histological/clinical observations from animal studies (in vivo). The text describes extensive physical bench testing, biocompatibility tests, and animal studies as part of the overall development and verification.
§ 870.4875 Intraluminal artery stripper.
(a)
Identification. An intraluminal artery stripper is a device used to perform an endarterectomy (removal of plaque deposits from arterisclerotic arteries.)(b)
Classification. Class II (performance standards).