Feed-forward frequency offset estimation for 32-QAM optical coherent detection.

Due to the non-rectangular distribution of the constellation points, traditional fast Fourier transform based frequency offset estimation (FFT-FOE) is no longer suitable for 32-QAM signal. Here, we report a modified FFT-FOE technique by selecting and digitally amplifying the inner QPSK ring of 32-QAM after the adaptive equalization, which is defined as QPSK-selection assisted FFT-FOE. Simulation results show that no FOE error occurs with a FFT size of only 512 symbols, when the signal-to-noise ratio (SNR) is above 17.5 dB using our proposed FOE technique. However, the error probability of traditional FFT-FOE scheme for 32-QAM is always intolerant. Finally, our proposed FOE scheme functions well for 10 Gbaud dual polarization (DP)-32-QAM signal to reach 20% forward error correction (FEC) threshold of BER=2×10-2, under the scenario of back-to-back (B2B) transmission.

Collaborative multicue fusion using the cross-diffusion process for salient object detection.

Salient object detection is very useful in a large variety of image and vision-related applications. A recent trend in salient object detection is to explore novel top-down visual cues and combine them with bottom-up saliency to improve the performance. However, a basic and important problem, i.e., how to effectively fuse multiple visual cues, has rarely been addressed in previous works. To this end, the paper presents a multicue fusion method using the cross-diffusion process (CDP) for salient object detection. The CDP algorithm is deployed to combine the affinity matrices constructed over individual visual cue channels, which is then embedded into a saliency propagation framework to accomplish salient object detection. Different from other multicue fusion strategies, our proposed approach allows for collaborative fusion, that is, the individual visual cues to be fused are able to interact and exchange information with each other during the fusion procedure, which can possibly correct the noise or corruption included in the individual visual cue channels, leading to more robust and effective fusion results. Intensive experiments on publicly available datasets demonstrate the effectiveness and superior performance of our proposed method.

Cauchy graph embedding based diffusion model for salient object detection.

Salient object detection has been a rather hot research topic recently, due to its potential applications in image compression, scene classification, image registration, and so forth. The overwhelming majority of existing computational models are designed based on computer vision techniques by using lots of image cues and priors. Actually, salient object detection is derived from the biological perceptual mechanism, and biological evidence shows that the spread of the spatial attention generates the object attention. Inspired by this, we attempt to utilize the emerging spread mechanism of object attention to construct a new computational model. A novel Cauchy graph embedding based diffusion (CGED) model is proposed to fulfill the spread process. Combining the diffusion model and attention prediction model, a salient object detection approach is presented through perceptually grouping the multiscale diffused attention maps. The effectiveness of the proposed approach is validated on the salient object dataset. The experimental results show that the CGED process can obviously improve the performance of salient object detection compared with the input spatial attention map, and the proposed approach can achieve performance comparable to that of state-of-the-art approaches.

Method for pan-tilt camera calibration using single control point.

The pan-tilt (PT) camera is widely used in video surveillance systems due to its rotatable property and low cost. The rough output of a PT camera may not satisfy the demand of practical applications; hence an accurate calibration method of a PT camera is desired. However, high-precision camera calibration methods usually require sufficient control points not guaranteed in some practical cases of a PT camera. In this paper, we present a novel method to online calibrate the rotation angles of a PT camera by using only one control point. This is achieved by assuming that the intrinsic parameters and position of the camera are known in advance. More specifically, we first build a nonlinear PT camera model with respect to two parameters Pan and Tilt. We then convert the nonlinear model into a linear model according to sine and cosine of Tilt, where each element in the augmented coefficient matrix is a function of the single variable Pan. A closed-form solution of Pan and Tilt can then be derived by solving a quadratic equation of tangent of Pan. Our method is noniterative and does not need features matching; thus its time efficiency is better. We evaluate our calibration method on various synthetic and real data. The quantitative results demonstrate that the proposed method outperforms other state-of-the-art methods if the intrinsic parameters and position of the camera are known in advance.

Directional support value of Gaussian transformation for infrared small target detection.

Robust small target detection is one of the key techniques in IR search and tracking systems for self-defense or attacks. In this paper we present a robust solution for small target detection in a single IR image. The key ideas of the proposed method are to use the directional support value of Gaussian transform (DSVoGT) to enhance the targets, and use the multiscale representation provided by DSVoGT to reduce the false alarm rate. The original image is decomposed into sub-bands in different orientations by convolving the image with the directional support value filters, which are deduced from the weighted mapped least-squares-support vector machines (LS-SVMs). Based on the sub-band images, a support value of Gaussian matrix is constructed, and the trace of this matrix is then defined as the target measure. The corresponding multiscale correlations of the target measures are computed for enhancing target signal while suppressing the background clutter. We demonstrate the advantages of the proposed method on real IR images and compare the results against those obtained from standard detection approaches, including the top-hat filter, max-mean filter, max-median filter, min-local-Laplacian of Gaussian (LoG) filter, as well as LS-SVM. The experimental results on various cluttered background images show that the proposed method outperforms other detectors.

A biologically-inspired framework for contour detection using superpixel-based candidates and hierarchical visual cues.

Contour detection has been extensively investigated as a fundamental problem in computer vision. In this study, a biologically-inspired candidate weighting framework is proposed for the challenging task of detecting meaningful contours. In contrast to previous models that detect contours from pixels, a modified superpixel generation processing is proposed to generate a contour candidate set and then weigh the candidates by extracting hierarchical visual cues. We extract the low-level visual local cues to weigh the contour intrinsic property and mid-level visual cues on the basis of Gestalt principles for weighting the contour grouping constraint. Experimental results tested on the BSDS benchmark show that the proposed framework exhibits promising performances to capture meaningful contours in complex scenes.

Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map.

This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate.

A novel biologically inspired local feature descriptor.

Local feature descriptor is a fundamental representation for image patch which has been extensively used in many computer vision applications. In this paper, different from state-of-the-art features, a novel biologically inspired local descriptor (BILD) is proposed based on the visual information processing mechanism of ventral pathway in human brain. The local features used for constructing BILD are extracted by a two-layer network, which corresponds to the simple-to-complex cell hierarchy in the primary visual cortex (V1). It works in a similar way as the simple cell and complex cell do to get responses by applying the lateral inhibition from different orientations and operating an improved cortical pooling. To enhance the distinctiveness of BILD, we combine the local features from different orientations. Extensive evaluations have been performed for image matching and object recognition. Experimental results reveal that our proposed BILD outperforms many widely used descriptors such as SIFT and SURF, which demonstrate its efficiency for representing local regions.

Biologically inspired multilevel approach for multiple moving targets detection from airborne forward-looking infrared sequences.

In this paper, a biologically inspired multilevel approach for simultaneously detecting multiple independently moving targets from airborne forward-looking infrared (FLIR) sequences is proposed. Due to the moving platform, low contrast infrared images, and nonrepeatability of the target signature, moving targets detection from FLIR sequences is still an open problem. Avoiding six parameter affine or eight parameter planar projective transformation matrix estimation of two adjacent frames, which are utilized by existing moving targets detection approaches to cope with the moving infrared camera and have become the bottleneck for the further elevation of the moving targets detection performance, the proposed moving targets detection approach comprises three sequential modules: motion perception for efficiently extracting motion cues, attended motion views extraction for coarsely localizing moving targets, and appearance perception in the local attended motion views for accurately detecting moving targets. Experimental results demonstrate that the proposed approach is efficient and outperforms the compared state-of-the-art approaches.

Robust method for infrared small-target detection based on Boolean map visual theory.

In this paper, we present an infrared small target detection method based on Boolean map visual theory. The scheme is inspired by the phenomenon that small targets can often attract human attention due to two characteristics: brightness and Gaussian-like shape in the local context area. Motivated by this observation, we perform the task under a visual attention framework with Boolean map theory, which reveals that an observer's visual awareness corresponds to one Boolean map via a selected feature at any given instant. Formally, the infrared image is separated into two feature channels, including a color channel with the original gray intensity map and an orientation channel with the orientation texture maps produced by a designed second order directional derivative filter. For each feature map, Boolean maps delineating targets are computed from hierarchical segmentations. Small targets are then extracted from the target enhanced map, which is obtained by fusing the weighted Boolean maps of the two channels. In experiments, a set of real infrared images covering typical backgrounds with sky, sea, and ground clutters are tested to verify the effectiveness of our method. The results demonstrate that it outperforms the state-of-the-art methods with good performance.

[Comparison of radial versus femoral approach for percutaneous coronary intervention in octogenarians with acute coronary syndrome].

OBJECTIVE: To evaluate the prognostic effects of radial artery access (RA) versus femoral artery access (FA) in octogenarians undergoing percutaneous coronary intervention (PCI) due to acute coronary syndrome (ACS). METHODS: From January 2008 to January 2013, 279 octogenarians with ACS underwent PCI. PCI was performed through RA in 125 patients and FA in another 154. Clinical and procedural characteristics, combined endpoints including death, acute myocardial infarction, stroke, and major bleeding, and peripheral vascular complications were obtained from both groups. RESULTS: The clinical baseline characteristics of two patient groups, including target vessel location, lesion type, number of implanted stents, fluoroscopy duration and utilization of contrast media had no statistical difference.Femoral approach was associated with a higher rate of ST elevation myocardial infarction (STEMI) than radial approach (27.9% vs 11.2%, χ² = 11.868, P < 0.05). Procedural rate of success, fluoroscopy duration and utilization of contrast media were equivalent with both approaches. Radial approach was associated with a higher crossover rate (10.4% vs 3.9%, χ² = 4.599, P < 0.05) to alternate access site compared with the femoral approach.No difference in combined endpoint during 30 days after PCI including death, acute myocardial infarction, stroke and major bleeding was found between two groups (P > 0.05).However, ambulation time (4.2 ± 0.9 vs 19.3 ± 4.1h, t = 40.381, P < 0.01), incidence of access site bleeding (2.4% vs 7.8%, χ² = 3.943, P < 0.05), hematoma (2.4% vs 9.1%, χ² = 5.398, P < 0.05), pseudoaneurysm (0.0% vs 5.2%, χ² = 4.950, P < 0.05) and vascular complications (4.8% vs 19.5%, χ² = 13.231, P < 0.01) were significantly lowered in radial approach group. Multivariate regression analysis identified radial approach as an independent negative predictor of postprocedural vascular complications (OR = 0.329, 95% CI: 0.124-0.517, P < 0.05).Female gender (OR = 1.955, 95% CI: 1.326-2.248, P < 0.05) and utilization of glycoprotein IIb/IIIa receptor antagonist (OR = 2.787, 95% CI: 2.435-3.071, P < 0.01) were independent predictors of postprocedural vascular complications. CONCLUSIONS: Compared with femoral approach, radial approach significantly reduces the vascular complications of PCI in octogenarians with ACS.However, PCI through RA is not associated with reduced combined endpoint at 30 days in octogerians with ACS.

The role of epicardial fat radiomic profiles for atrial fibrillation identification and recurrence risk with coronary CT angiography.

OBJECTIVES: Fat radiomic profile (FRP) was a promising imaging biomarker for identifying increased cardiac risk. We hypothesize FRP can be extended to fat regions around pulmonary veins (PV), left atrium (LA), and left atrial appendage (LAA) to investigate their usefulness in identifying atrial fibrillation (AF) and the risk of AF recurrence. METHODS: We analysed 300 individuals and grouped patients according to the occurrence and types of AF. We used receiver operating characteristic and survival curves analyses to evaluate the value of imaging biomarkers, including fat attenuation index (FAI) and FRP, in distinguishing AF from sinus rhythm and predicting post-ablation recurrence. RESULTS: FRPs from AF-relevant fat regions showed significant performance in distinguishing AF and non-AF with higher AUC values than FAI (peri-PV: FRP = 0.961 vs FAI = 0.579, peri-LA: FRP = 0.923 vs FAI = 0.575, peri-LAA: FRP = 0.900 vs FAI = 0.665). FRPs from peri-PV, peri-LA, and peri-LAA were able to differentiate persistent and paroxysmal AF with AUC values of 0.804, 0.819, and 0.694. FRP from these regions improved AF recurrence prediction with an AUC of 0.929, 0.732, and 0.794. Patients with FRP cut-off values of ≥0.16, 0.38, and 0.26 had a 7.22-, 5.15-, and 4.25-fold higher risk of post-procedure recurrence, respectively. CONCLUSIONS: FRP demonstrated potential in identifying AF, distinguishing AF types, and predicting AF recurrence risk after ablation. FRP from peri-PV fat depot exhibited a strong correlation with AF. Therefore, evaluating epicardial fat using FRP was a promising approach to enhance AF clinical management. ADVANCES IN KNOWLEDGE: The role of epicardial adipose tissue (EAT) in AF had been confirmed, we focussed on the relationship between EAT around pulmonary arteries and LAA in AF which was still unknown. Meanwhile, we used the FRP to excavate more information of EAT in AF.

Effect of Vigileo/FloTrac System-Guided Aggressive Hydration in Acute Myocardial Infarction Patients to Prevent Contrast-Induced Nephropathy After Urgent Percutaneous Coronary Intervention.

Tailored hydration strategies appear to provide an effective solution for preventing contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI). The Vigileo/FloTrac system could predict the patients' fluid responsiveness and tolerance to hydration. This prospective multicenter, randomized controlled, open-label study evaluated the efficacy of aggressive hydration guided by the Vigileo/FloTrac system for CIN prevention in patients with acute myocardial infarction (AMI). This trial enrolled patients with AMI undergoing urgent PCI, and these patients were randomized (1:1) to receive either aggressive hydration guided by Vigileo/FloTrac system (intervention group) or general hydration (control group). Patients with AMI in the intervention group received a loading dose of saline, and the hydration speed was adjusted according to the change of Vigileo/FloTrac index. The primary end point is CIN, which was defined as a >25% or >0.5 mg/100 ml increase in serum creatinine compared with baseline during the first 72 hours after urgent PCI. This trial was registered in ClinicalTrials.gov (NCT04382313). A total of 344 patients with AMI were enrolled and randomized in our trial, and the baseline characteristics, including risk factors of CIN, of the Vigileo/FloTrac-guided hydration group (n = 173) and control group (n = 171) were well balanced (all p >0.05). The total hydration volume in Vigileo/FloTrac-guided hydration group was significantly much more than control group (1,910 ± 600 vs 440 ± 90 ml, p <0.001). The incidence of CIN in the Vigileo/FloTrac-guided hydration group was significantly decreased than that in the control group (12.1% [21/173] vs 22.2% [38/171], p = 0.013). There was not significantly different in the incidence of acute heart failure after PCI (9.2% [16/173] vs 7.6% [13/171], p = 0.583). The incidence of main adverse cardiovascular events in the Vigileo/FloTrac-guided hydration group was lower than that in the control group but without statistically difference (30 events [17.3%] vs 38 events [22.2%], p = 0.256). In conclusion, Vigileo/FloTrac system-guided aggressive hydration could effectively decrease the risk of CIN for patients with AMI undergoing urgent PCI and avoid attack of acute heart failure at the same time.

Saliency detection using midlevel visual cues.

This Letter presents a computational model for saliency detection in natural images. While existing approaches usually make use of low-level or high-level visual features for establishing the saliency models, our method relies on midlevel visual cues, i.e., the superpixel representation of the image. In the proposed approach, the given image is first partitioned into superpixels. A fully connected superpixel graph is then constructed, and the random walk on the graph is adopted to measure saliency. In addition, a scheme based on multiple segmentations is used for multiscale processing. Our model has the advantage of generating high-resolution saliency maps with well-defined object borders. Experimental results on publicly available datasets demonstrate the proposed model can outperform the compared state-of-the-art saliency models.

From Noise Addition to Denoising: A Self-Variation Capture Network for Point Cloud Optimization.

Point clouds obtained from 3D scanners are often noisy and cannot be directly used for subsequent high-level tasks. In this paper, we propose a novel point cloud optimization method capable of denoising and homogenizing point clouds. Our idea is based on the assumption that the noise is generally much smaller than the effective signal. We perform noise perturbation on the noisy point cloud to get a new noisy point cloud, called self-variation point cloud. The noisy point cloud and self-variation point cloud have different noise distribution, but the same point cloud distribution. We compute the potential commonality between two noisy point clouds to obtain a clean point cloud. To implement our idea, we propose a Self-Variation Capture Network (SVCNet). We perturb the point cloud features in the latent space to obtain self-variation feature vectors, and capture the commonality between two noisy feature vectors through the feature aggregation and averaging. In addition, an edge constraint module is introduced to suppress low-pass effects during denoising. Our denoising method does not take into account the noise characteristics, and can filter the drift noise located on the underlying surface, resulting in a uniform distribution of the generated point cloud. The experimental results show that our algorithm outperforms the current state-of-the-art algorithms, especially in generating more uniform point clouds. In addition, extended experiments demonstrate the potential of our algorithm for point clouds upsampling.

Intracoronary artery retrograde thrombolysis combined with percutaneous coronary interventions for ST-segment elevation myocardial infarction complicated with diabetes mellitus: A case report and literature review.

Background: The management of a large thrombus burden in patients with acute myocardial infarction and diabetes is still a worldwide problem. Case presentation: A 74-year-old Chinese woman presented with ST-segment elevation myocardial infarction (STEMI) complicated with diabetes mellitus and hypertension. Angiography revealed massive thrombus formation in the mid-segment of the right coronary artery leading to vascular occlusion. The sheared balloon was placed far from the occlusion segment and urokinase (100,000 u) was administered for intracoronary artery retrograde thrombolysis, and thrombolysis in myocardial infarction (TIMI) grade 3 blood flow was restored within 7 min. At last, one stent was accurately implanted into the culprit's vessel. No-reflow, coronary slow flow, and reperfusion arrhythmia were not observed during this process. Conclusion: Intracoronary artery retrograde thrombolysis (ICART) can be effectively and safely used in patients with STEMI along with diabetes mellitus and hypertension, even if the myocardial infarction exceeds 12 h (REST or named ICART ClinicalTrials.gov number, ChiCTR1900023849).

IntraCoronary Artery Retrograde Thrombolysis vs. Thrombus Aspiration in ST-Segment Elevation Myocardial Infarction: Study Protocol for a Randomized Controlled Trial.

Background: Type 2 diabetes (T2DM) is a major risk factor for myocardial infarction. Thrombus aspiration was considered a good way to deal with coronary thrombus in the treatment of acute myocardial infarction. However, recent studies have found that routine thrombus aspiration is not beneficial. This study is designed to investigate whether intracoronary artery retrograde thrombolysis (ICART) is more effective than thrombus aspiration or percutaneous transluminal coronary angioplasty (PTCA) in improving myocardial perfusion in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). Methods/Design: IntraCoronary Artery Retrograde Thrombolysis (ICART) vs. thrombus aspiration or PTCA in STEMI trial is a single-center, prospective, randomized open-label trial with blinded evaluation of endpoints. A total of 286 patients with STEMI undergoing PPCI are randomly assigned to two groups: ICART and thrombus aspiration or PTCA. The primary endpoint is the incidence of >70% ST-segment elevation resolution. Secondary outcomes include distal embolization, myocardial blush grade, thrombolysis in myocardial infarction (TIMI) flow grade, and in-hospital bleeding. Discussion: The ICART trial is the first randomized clinical trial (RCT) to date to verify the effect of ICART vs. thrombus aspiration or PTCA on myocardial perfusion in patients with STEMI undergoing PPCI. Clinical Trial Registration: [https://www.chictr.org.cn/], identifier [ChiCTR1900023849].

Intracoronary artery retrograde thrombolysis for ST-segment elevation myocardial infarction with a tortuous coronary artery: A case report and review of the literature.

Background: How to deal with large thrombus burdens of culprit's blood vessel remains a great challenge in the treatment of acute myocardial infarction. Case presentation: A 32-year-old Chinese man was diagnosed with ST-segment elevation myocardial infarction (STEMI). Coronary angiography revealed that the distal end of a tortuous left circumflex was completely occluded by a large amount of thrombus. Cutted balloon-directed intracoronary artery retrograde thrombolysis (ICART) with urokinase led to the restoration of coronary blood flow. Because there was no obvious plaque rupture or artery stenosis in the coronary artery, it was only dilated, and no stent was implanted. Conclusion: Cutted balloon-directed ICART can be performed effectively and safely in some STEMI patients with tortuous coronary vessels and large thrombus. (REST or named ICART ClinicalTrials.gov number, ChiCTR1900023849).

Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: The CHANGE Trial.

Background Nicorandil was reported to improve microvascular dysfunction and reduce reperfusion injury when administered before primary percutaneous coronary intervention. In this multicenter, prospective, randomized, double-blind clinical trial (CHANGE [Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention]), we investigated the effects of nicorandil administration on infarct size in patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention. Methods and Results A total of 238 patients with ST-segment-elevation myocardial infarction were randomized to receive intravenous nicorandil (n=120) or placebo (n=118) before reperfusion. Patients in the nicorandil group received a 6-mg intravenous bolus of nicorandil followed by continuous infusion at a rate of 6 mg/h. Patients in the placebo group received the same dose of placebo. The predefined primary end point was infarct size on cardiac magnetic resonance (CMR) imaging performed at 5 to 7 days and 6 months after reperfusion. CMR imaging was performed in 201 patients (84%). Infarct size on CMR imaging at 5 to 7 days after reperfusion was significantly smaller in the nicorandil group compared with the placebo (control) group (26.5±17.1 g versus 32.4±19.3 g; P=0.022), and the effect remained significant on long-term CMR imaging at 6 months after reperfusion (19.5±14.4 g versus 25.7±15.4 g; P=0.008). The incidence of no-reflow/slow-flow phenomenon during primary percutaneous coronary intervention was much lower in the nicorandil group (9.2% [11/120] versus 26.3% [31/118]; P=0.001), and thus, complete ST-segment resolution was more frequently observed in the nicorandil group (90.8% [109/120] versus 78.0% [92/118]; P=0.006). Left ventricular ejection fraction on CMR imaging was significantly higher in the nicorandil group than in the placebo group at both 5 to 7 days (47.0±10.2% versus 43.3±10.0%; P=0.011) and 6 months (50.1±9.7% versus 46.4±8.5%; P=0.009) after reperfusion. Conclusions In the present trial, administration of nicorandil before primary percutaneous coronary intervention led to improved myocardial perfusion grade, increased left ventricular ejection fraction, and reduced myocardial infarct size in patients with ST-segment-elevation myocardial infarction. Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT03445728.

[Tirofiban improved the prognosis of senior acute coronary syndrome patients received percutaneous coronary intervention].

OBJECTIVE: To examine if tirofiban may improve the prognosis in aged acute coronary syndrome (ACS) patients received percutaneous coronary intervention (PCI). METHODS: Three hundred and twenty-five ACS patients (age ≥ 60 years), all received drug-eluting stents implantation, were assigned into tirofiban group (n = 210) to receive tirofiban+aspirin and clopidogrel and control group (n = 115) to received aspirin and clopidogrel only. The incidence of thrombolysis in myocardial infarction (TIMI) grade 3 after PCI, in-stent thrombosis, slight/severe bleeding, platelet decrease, myocardial infarction (MI) and target vessel revascularization (TVR) within 30 days and 12 months after PCI and 30 days and 12 months mortality post PCI. RESULTS: In comparison with the control group, the tirofiban group had significantly higher TIMI grade 3 flow after PCI (99.05% vs. 94.78%, P < 0.05), lower in-stent thrombosis (0.47% vs. 2.61%, P < 0.05), as well as lower mortality, MI, and TVR in 30 days and 12 months after PCI (30 days: 0, 0.47% and 0.47% vs. 2.61%, 3.48% and 2.61%; 12 months: 0, 0.47% and 0.47% vs. 2.61%, 5.22% and 5.22%, P < 0.05 or P < 0.01). No significant difference was found (both P > 0.05) in slight bleeding (7.14% vs. 4.35%) and severe bleeding (0 vs. 0) between tirofiban group and control group. A slight difference in thrombocytopenia was found between tirofiban group and control group (0.95% vs. 0), but it failed to reach the level of statistical significance (P > 0.05). CONCLUSIONS: Tirofiban may improve the TIMI grade flow in senior ACS patients after PCI. It also decreases the incidence of in-stent thrombosis, mortality, MI, and TVR in 30 days and 12 months after PCI, without causing increase in severe bleeding and platelet penia. Therefore, it may improve the short/long-term prognosis for these patients.