DirectX 11 LINELIST_TOPOLOGY uncompleted 2D rectangle at left-top coordinates

Question

I'm doing something with DirectX 11 and came to a rectagle drawing (empty, non-colored), seemed simple for me at start (linelist_topology, 8 indices) but when I have it on the screen I see that my rectangle is kinda incomleted at left-top coordinate, there is a point of a background color there, the code is not complicated at all, vertices are 2D space:

SIMPLEVERTEX gvFrameVertices[4]=
{XMFLOAT3(0.0f,0.0f,1.0f),XMFLOAT2(0.0f, 0.0f),
XMFLOAT3(1.0f, 0.0f, 1.0f), XMFLOAT2(1.0f, 0.0f),
XMFLOAT3(1.0f, -1.0f, 1.0f), XMFLOAT2(1.0f, 1.0f),
XMFLOAT3(0.0f, -1.0f, 1.0f), XMFLOAT2(0.0f, 1.0f)};

indices:

WORD gvRectangularIndices[8] = { 0, 1, 1, 2, 2, 3, 3, 0 };

Shader just returns given color in constant buffer:

float4 PS_PANEL(PS_INPUT input) : SV_Target
{
    return fontcolor;
}

Function code itself:

VOID rectangle(INT _left, INT _top, INT _width, INT _height, XMFLOAT4 _color)
{
    XMMATRIX scale;
    XMMATRIX translate;
    XMMATRIX world;

scale     = XMMatrixScaling( _width, _height, 1.0f );
translate = XMMatrixTranslation(_left, gvHeight - _top, 1.0f); 
world     = scale * translate;

gvConstantBufferData.world = XMMatrixTranspose(world);
gvConstantBufferData.index = 1.0f;
gvConstantBufferData.color = _color;

gvContext->PSSetShader(gvPanelPixelshader, NULL, 0);
gvContext->UpdateSubresource(gvConstantBuffer, 0, NULL, &gvConstantBufferData, 0, 0 );
gvContext->IASetIndexBuffer(gvLinelistIndexBuffer, DXGI_FORMAT_R16_UINT, 0);
gvContext->IASetPrimitiveTopology( D3D11_PRIMITIVE_TOPOLOGY_LINELIST );

gvContext->DrawIndexed(8, 0, 0);

gvContext->IASetIndexBuffer(gvTriangleslistIndexBuffer, DXGI_FORMAT_R16_UINT, 0);
gvContext->IASetPrimitiveTopology( D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST );

};

gvHeight - _top - I'm using orthographic matrix for projection, so the coordinate center is at left-bottom, that why need to substract for proper Y coordinate.

gvOrthographicProjection = XMMatrixOrthographicOffCenterLH( 0.0f, gvWidth, 0.0f, gvHeight, 0.01f, 100.0f );

Do you have any idea what can cause this pointal incompletness of a rectangle in my case or I need to supply more code info (don't really want to link lines of the whole initializations cause they seem very obvious and simple for me, done for /at c++ and directx amateur level :) Thank you:)